//被人误导了靠
/*
#include<iostream>
#include<cstdio>
#include<cstring>

using namespace std;

int n,ans,flag;
char a[105];

int main () {
	cin>>n>>a;
	char t=a[0];
	for(int i=0;i<n;i++)
	{
		if(t==a[i] && t=='x')
		{
			flag++;
			if(flag>=3)
				ans++;
		}
		else
		{
			t=a[i];
				flag=1;
		}

	}
	cout<<ans<<endl;
	return 0;
}*/
#include<bits/stdc++.h>

using namespace std;

char a[105];
int n,ans;

int main () {
	cin>>n>>a;
	for(int i=0;i<n;i++)
	{
		if(a[i]=='x' && a[i+1]=='x' && a[i+2]=='x')
		{
			//flag=1;
			ans++;
		}
	}
	cout<<ans<<endl;
	return 0;
}

#include <iostream>
#include <string>
using namespace std;
void main()
{
	int n, p = 0;
	char a[100];
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cin >> a[i];
		if (a[i] == 'x')
		{
			p++;
		}
	}
	int k = 0;
	if (p < 2)
	{
		cout << 0;
	}
	else
	{
		for (int i = 0; i < n - 2; i++)
		{
			if (a[i] == 'x' && a[i + 1] == 'x' && a[i + 2] == 'x')
			{
				k++;
			}
		}
		cout << k;
	}
	;
}

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<set>
using namespace std;
int main()
{
	int n; char s[110];
	cin >> n;
	cin >> s;
	int t = 0, c = 0;
	for (int i = 0; i < n; i++)
	{
		if (s[i] == 'x')
			t++;
		if (s[i] != 'x')
			t = 0;
		if (t == 3)
		{
			t = 2;
			c++;
		}
	}
	cout << c << endl;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int ans;
char a[102];
int main()
{
	int n;
	cin>>n>>a;
	for(int i=2;i<n;i++)
	{
		if(a[i]=='x'&&a[i-1]=='x'&&a[i-2]=='x')
			ans++;
	}
	cout<<ans;
}

#include<iostream>
using namespace std;
int main () {
    int t=0,n;
    string s;
    cin>>n>>s;
    for(int i=2;i<s.size();i++){
            if(s[i]=='x' && s[i-1]=='x' && s[i-2]=='x')t++;
    }
    cout<<t;
    return 0;
}

#include <iostream>

using namespace std;

int main()
{
	int n, sum=0;
	char let[100]={};
	cin>>n;
	for(int i=0; i<n; ++i)
	{
		cin>>let[i];
	}
	for(int i=0; i<n; ++i)
	{
		if((let[i]=='x')&&(let[i+1]=='x')&&(let[i+2]=='x'))
		{
			sum++;
		}
	}
	cout<<sum;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int n;
    cin>>n;
    string s;
    cin>>s;

    int ans=0,p=0;

    for(int i=0;i<n;i++)
    {
        if(s[i]=='x'){
            p++;
        }
        else{
            if(p>2) ans+=p-2;
            p=0;
        }
    }
    if(p>2) ans+=p-2;
    cout<<ans;
    return 0;
}

#include<iostream>
#include<string>
#include<algorithm>
#include<set>
using namespace std ;
void main()
{
	int n;
	cin>>n;
	int k=0;
	int counter=0;
	int con=0;
	char a[100];
	for(int i=0;i<n;i++)
	{
		cin>>a[i];

	}
	for(int i=0;i<n;i++)
	{

		if(a[i]=='x')
		{
		counter++;

		}
		else
		{
			counter=0;
			continue;

		}
		if(counter>=3)
		{
			con++;

		}
	}

cout<<con<<endl;
}

#include<bits/stdc++.h>
using namespace std;
#define ll long long int

int main()
{
    ll i,j,n,m,ans,sum=0,temp,diff,count=0,test,x,y,len;
    string str1,str2;
    cin>>n;
    cin.ignore();
    getline(cin,str1);
    for(i=0;i<n;i++)
    {
        if(str1[i]=='x')
        {
            count++;
        }
        else if(str1[i]!='x')
        {
            if(count>2){sum=sum+count-2;}
            count=0;
        }
    }
    if(count>2)
    {
        sum=sum+count-2;
    }
    cout<<sum<<endl;
}

#include<iostream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    std::string s;
    cin>>s;
     int nox=0,cnt=0;
     for(int i=0;i<n;i++)
     { if(s[i]=='x')
        {cnt++;
        if(cnt>2)
            {nox++;

            }
        }
        else
            cnt=0;
     }
 cout<<nox<<endl;

}

#include <iostream>
using namespace std;
int main()
{
    int a,c=0;
    cin>>a;
    string b;
    cin>>b;
    for(int u=0 ; u<=(a-3);u++)
    {if(b[u]=='x' && b[u+1]=='x' && b[u+2]=='x')
    {c++;}}
    cout<<c;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,t,c=0,d=0;
    string s;
    cin>>n;
    cin>>s;
    for(int i=0; i<s.size(); i++)
    {

        if(s[i]=='x')
        {
            c++;
            if(i==s.size()-1)
            {
                if(c>=3)
                d=d+(c-2);
            }
        }
        else if(s[i]!='x')
        {
            if(c>=3)
            {

                d=d+(c-2);
            }
            c=0;
            continue;

        }
    }
    if(c==s.size())
    {
        cout<<c-2<<endl;
    }
    else
        cout<<d<<endl;
}

#include<bits/stdc++.h>
using namespace std;

int main(){
    int n, ans=0, a=0;
    string s;
    cin >> n >> s;
    for(int i=0;i<n;i++){
        if(s[i]=='x')
        {
            a++;
            if(a>2)
                ans++;
        }
        else a=0;
    }
    cout << ans << endl;
return 0;
}

#include<bits/stdc++.h>

using namespace std;
const int maxn=2e5;
char s[maxn];
int a[maxn];
int main()
{
    int n;
    scanf("%d",&n);
    scanf("%s",s+1);
    int cnt=0;
    for(int i=1;i<=n;i++)
    {
        int flag=0;
        int temp=0;
        while(s[i]=='x')
        {
            flag=1;
            temp++;
            i++;
        }
        if(flag)
        {
            if(temp>=3)
            {
                a[++cnt]=temp;
            }
            i--;
        }
    }
    int ans=0;
    for(int i=1;i<=cnt;i++)
    {
        ans+=a[i]-2;
    }
    printf("%d\n",ans);
}

#include<bits/stdc++.h>
#define Ishaan using
#define M namespace
#define Tandel std
#define tt long long int t;cin>>t;while(t--)
#define fir(i, j, k) for (int i=j; i<k; i++)
#define fr(i,j,k) for (int i=j ; i<=k ; i++)
#define rev(i, j, k) for(int i=j; i>=k; i--)
#define REP(i, k) for(int i = (0); i < (k); i++ )
#define RREP(i, k) for(int i = j; i >= (k); i-- )
#define FOREACH(it, l) for(auto it=l.begin(); it != l.end(); it++)
#define mp make_pair
#define pb push_back
#define RESET(a, b) memset(a, b, sizeof(a))
#define INF (2e+18)
#define EPS (int)1e-9
#define PI acos(-1)
#define MOD 1000000007

Ishaan M Tandel;

typedef pair<int, int> pii;
typedef pair<int, pii> piii;
typedef vector<int> vi;
typedef vector<string> vs;
typedef vector<pii> vii;
typedef vector<piii> viii;
typedef long long int ll;
typedef unsigned long long int ull;
typedef string s;
typedef float ff;
typedef double dd;

void imt()
{
        ll n;
        cin>>n;

        s a;

        cin>>a;
        ll ans=0;
        ll c=0;

        ll sum=0;

        fir(i,0,n)
        {
            if(a[i]=='x')
            {
                c++;
            }
            else
            {
                if(c>=3)
                {
                    ans += c-2;
                }
                c=0;
            }

        }

        if(c>=3)
        {
            ans += c-2;
        }

        cout<<ans<<endl;
}

int main() {
    #ifndef ONLINE_JUDGE
        freopen ("input.txt","r",stdin);
        freopen ("output.txt","w",stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int TC = 1;
    //cin >> TC;

    REP(tc, TC)
    {
        imt();

    }
    return 0;
}

#include<bits/stdc++.h>
#define ll long long int
#define YES cout<<"YES"<<endl
#define NO cout<<"NO"<<endl
#define yes cout<<"yes"<<endl
#define no cout<<"no"<<endl

using namespace std;

int main()
{
    int n,l,cnt=0,c=0;
    string s;
    cin>>n>>s;
    l=s.size();

    for(int i=0; i<l-2; i++)
    {
        if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x')
        {
            c++;
        }
    }
    cout<<c<<endl;

}

#include <iostream>

using namespace std;

int main(){
	int n , brojac=0 , brojac1=0;
	char a;
	cin>>n;
	for (int i=0;i<n;i++)
	{
		cin>>a;
		if (a=='x') brojac++;
		else brojac=0;
		if (brojac>=3) brojac1++;
	}

	cout<<brojac1;
	return 0;
}

#include <iostream>
#include <string>

using namespace std;

string v;

int main() {
    int n, cnt = 0;
    cin >> n >> v;
    int i = 0;
    while ( i < n ) {
        int j = i, cj;
        bool ok = false;
        while ( j < n && v[j] == 'x' )
            j ++;
        if ( j - i - 2 < 0 ) {
            cj = j;
            j = i + 2;
            ok = true;
        }
        cnt += j - i - 2;
        if ( ok )
            j = cj;
        i = j + 1;
    }
    cout << cnt << "\n";
    return 0;
}

#include<cstdio>
char tmp[100];
int main()
{
	int n;
	int ans=0;
	scanf("%d",&n);
	scanf("%s",tmp);
	for(int i=2;i<n;i++)
	{
		if(tmp[i]=='x'&&tmp[i-1]=='x'&&tmp[i-2]=='x')
		{
			ans++;
		}
	}
	printf("%d\n",ans);
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int a,i,j=0,k=0,res,x;
    string b;
    cin>>a>>b;
    for(i=0;i<a;i++)
    {
        if(b[i]=='x'){j++;}
        else{if(j>2){k+=(j-2);}j=0;}
    }
    x=j;res=k;
    if(x>2){res+=x-2;}
    cout<<res;
}

#include <iostream>
#include <string>
// #include <cstdlib>
// #include <cmath>
#include <array>
// #include <vector>
// #include <algorithm>
// #include <set>
// #include <map>

using namespace std;

int main(){
	int n;
	cin >> n;

	string error;
	cin >> error;

	int remove_x = 0;
	int xcnt = 0;

	for(int i = 0; i < n; i++){
		if(error[i] == 'x'){
			xcnt++;
		}
		else{
			// cout << "x=" << xcnt << endl;
			if(xcnt >= 3){
				remove_x += (xcnt - 2);
			}
			xcnt = 0;
		}

	}
	if(xcnt >= 3){
		remove_x += (xcnt - 2);
	}
	cout << remove_x << endl;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a,p=0,q=0;
    cin>>a;
    char s;
    for(int i=0;i<a;i++)
    {
        cin>>s;
        if(s=='x')
        {
            p++;
             if(p>2)
        {
            q++;
        }
        }

        else
        {
            p=0;
        }
    }
   cout<<q<<endl;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
char s[105];
int main(){
    int n;
    scanf("%d",&n);
    scanf("%s",s);
    int len=strlen(s);
    int sum=0;
    for(int i=0;i<=len-3;i++){
        int j;
        for(j=i;j<i+3;j++){
            if(s[j]!='x'){
                break;
            }
        }
        if(j==i+3) sum++;
    }
    printf("%d\n",sum);
}

#include <iostream>
#include <string>
#include <vector>

using namespace std;

int main()
{
	int s=0, n, i;
	string str;
	cin >> n;
	cin >> str;
	for (i = 1;i < n - 1;i++)
	{
		if (str[i - 1] == 'x'&&str[i] == 'x'&&str[i + 1] == 'x')
			s++;
	}
	cout << s;
	getchar();
	getchar();
	return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
	char a[102];
	int n, s = 0, m = 0; cin >> n; cin.ignore();
	cin.getline(a, n + 1);
	for (int i = 0; i < n; i++)
	{
		if (a[i] != 'x')
		{
			s = 0; continue;
		}
		else s++;
		if (s == 3)
		{
			m++;
			if (a[i + 1] == 'x') s = 2; else s = 0;
		}
	}
	cout << m;
}

#include <iostream>

using namespace std;

int main()
{
  int k,n,i,j=0,x;
  string s;
  cin>>k;
  cin>>s;
 // if(s.find("xxx")==4294967295) cout<<0; else
  //  {
    i=0;
  while(i<k)
   {

       x=s.find("xxx");
       if(s.find("xxx")==4294967295)break; else{

       s[x]='*'; j++;
   // cout<<s;

       i=x+1;

       }

       }
cout<<j;
   }

#include<bits/stdc++.h>
using namespace std ;
int n,i,cnt;
char str[101];

int main(){

cin>>n;
for(i=0;i<n;++i)
    cin>>str[i];

for(i=0;i<n;++i){
    if(i+2<=n-1){
        if(str[i]=='x' && str[i+1]=='x'&& str[i+2]=='x'){
            cnt++;
        }
    }}
    cout<<cnt<<endl;

return 0;}

#include<iostream>
#include<string>
#include<cmath>
#include<algorithm>
using namespace std;
int main() {
	bool b;
	int n, counter = 0, ANS = 0;
	string s;
	cin >> n >> s;
	for (int i = 0; i < s.length(); ++i) {
		if (s[i] != 'x')
			b = 0;
		else
			b = 1;
		if (b)
			counter++;
		else {
			if (counter >= 3)
				ANS += counter - 2;
			counter = 0;
		}
		if (i == s.length() - 1 && counter > 0 && counter >= 3)
			ANS += counter - 2;
	}
	cout << ANS;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;

int main(){

    int n;
    cin>>n;
    string s="";
    string x;

   for(int i=0;i<n;i++){
      cin>>x;
      s=s+x;
   }

    int c=0;

    if(n<=2){
        cout<<0;
    }
    else{
        for(int i=2;i<n;i++){
            if(s[i]=='x'){
                if(s[i-1]=='x')
                if(s[i-2]=='x')
                    c++;
        }
    }

    cout<<c;
    }
    return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{

	int n;
	cin >> n;
	string str;
	cin >> str;

	int flag = 0, count = 0;
	for (int i = 0; i < n; i++) {
		if (str[i] == 'x') flag++;
		else flag = 0;
		if (flag == 3) {
			flag--;
			count++;
		}
	}
	cout << count << endl;
	return 0;
}

#include <iostream>
using namespace std ;
int main(){
	int n,count=0;
	cin>>n;
	char *a;
	a=new char[n];
	for(int i=0 ; i<n ; i++){
		cin>>a[i];
	}
	for(int i=0 ; i<n ; i++){
		if(a[i]=='x' && a[i+1]=='x' && a[i+2]=='x'){
			count++;
		}
	}
	cout<<count;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,ans=0,a=0;
    string s;
    cin>>n>>s;
    for(int i=0; i<n; i++)
    {
        if(s[i]=='x')
        {
            a++;
            if(a>2)
                ans++;
        }
        else
            a=0;
    }
    cout<<ans<<endl;
    return 0;
}

#include <iostream>

using namespace std;

int main(){
    short n, r, s = 0; string st;
    cin >> n >> st;
    if (st[0] == 'x') r = 1; else r = 0;
    for (int i = 1; i < n; i++){
        if (st[i] == 'x') r++; else{
            if (r > 2) s += r - 2;
            //cout << s << r << endl;
            r = 0;
        }
    }
    if (r > 2) s += r - 2;
    cout << s;
    return 0;
}

#include <iostream>
#include <string.h>
#include <algorithm>
using namespace std;
int n,num=0,ans=0;
char book[105];
int main()
{
	cin>>n;
	cin>>book;
	for(int i=0;i<n;i++)
	{
		if(book[i]=='x')
			num++;
		else
		{
			if(num>=3)
				ans+=num-2;
			num=0;
		}
		if(i==n-1)
		{
			if(num>=3)
				ans+=num-2;
		}
	}
	cout<<ans;

	return 0;
 }

#include<iostream>
#include<vector>
#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,i=0,k=0,jk=0,x=0;
    cin>>n;
    string s;
    cin>>s;
    int z[n]={1};
    for(i=0;i<n;i++)
    {
        z[i]=1;
    }
    for(i=0;i<n-1;i++)
    {
        if(s[i]=='x' && s[i+1]=='x')
        {
            z[k]++;
        }
        if(s[i+1]!='x')
        {
            k++;
        }
    }
    cout<<endl;
    for(i=0;i<k+1;i++)
    {
        if(z[i]>2)
        {
            jk=jk+z[i]-2;
        }
    }
    cout<<jk;
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    cin.sync_with_stdio(0);
    cin.tie(0);

    int n, xxx = 0;
    string file;
    cin >> n >> file;

    for (int i = 0; i < n - 2; i++)
    {
        if (file.substr(i, 3) == "xxx") ++xxx;
    }

    cout << xxx << '\n';
    return 0;
}

#include <iostream>
#include <vector>
#include <string>

using namespace std;

int main()
{
	int length = 0;
	cin >> length;
	string input;
	cin >> input;
	int count = 0;
	int sumX = 0;
	for (int i = 0; i < length; i++)
	{
		if (input[i] == 'x')count++;
		if (input[i] != 'x')count = 0;
		if (count > 2)sumX++;
	}
	cout << sumX;
}

#include<stdio.h>
#include<string.h>
#include<math.h>
/* *********************************************************** */

#include<bits/stdc++.h>
using namespace std;

//************************************************************ */

#define fin             freopen("in.txt","r",stdin)
#define fou             freopen("ou.txt","w",stdout)
#define ll              long long
#define ull             unsigned long long
#define sc              scanf
#define pr              printf
#define FastIO	        ios_base::sync_with_stdio(false); cin.tie(NULL)
#define mset(v,d)       memset(v, d, sizeof(v))
#define sc1(a)          sc("%d",&a)
#define sc2(a,n)        sc("%d%d",&a,&n)
#define sc3(a,n,m)      sc("%d%d%d",&a,&n,&m)
#define pr1(a)          pr("%d\n",a)
#define so(a,n)         sort(a,a+n)
#define br              puts("")
#define pb(a)           push_back(a)
#define pbk(a)          pop_back()
#define ln              length()
#define sz              size()
#define pr2(a,n)        pr("%d %d\n",a,n)
#define rn              return
#define For(i,lo,n) 	for(int i = lo; i < n; i++)
#define Forr(i,lo,n) 	for(int i = n; i >= lo; i--)
#define Frl(i,n) 	    for(int i = 0; i < n; i++)
#define acin(a,n)  	    for(int i = 0; i < n; i++)  cin>>a[i]
#define ain(a,n)  	    for(int i = 0; i < n; i++)  scanf("%d",&a[i])
#define aou(a,n)        for(int i = 0; i < n; i++)  pr("%d ",a[i])

typedef vector<int> vi;
typedef vector <ll> vll;
typedef map<string, int> msi;

//*************************************************************/

int n,m,i,j,o=0;

void fm(){
    #ifndef ONLINE_JUDGE
        fin;
       // fou;
    #endif
}

//map<string, int>v;
//vector<int> vv;
//int a[4];
typedef struct pai{
    int x,y;

}pa;
//typedef pai pa
int a[100001],b[100],d[100];
int main()
{
    FastIO;
    cin>>n;
    string a;
    cin>>a;
    //cout<<a;
    int cc=0,c=0;
    for(i=0;i<n-2;i++)
    {
        if(a[i]=='x')
        {
            if(a[i]==a[i+1]&&i+2<n)
            {
                cc=2;
                for(j=i+2;j<n;j++)
                {
                    if(a[j]!='x')break;
                    cc++;

                }
                //pr1(cc);
                if(cc>2)c+=(cc-2);
                i=j-1;
            }
        }
    }
    //printf("%d\n",c);
    cout<<c<<endl;
    rn 0;

}

#include<vector>
#include<iostream>
#include<string>
#include<algorithm>
#include<map>
using namespace std;

int main()
{
    int len;
    string file_name;

    cin>>len;
    cin>>file_name;

    int to_delete = 0;
    int consecutive_x = 0;

    for (int idx = 0; idx < len; idx++)
    {
        if (file_name[idx] == 'x')
        {
            if (consecutive_x == 2)
            {
                ++to_delete;
            }
            else
            {
                ++consecutive_x;
            }
        }
        else
        {
            consecutive_x = 0;
        }
    }

    cout<<to_delete;

    return 0;
}

#include<iostream>
using namespace std;

int main(){
int n, count = 0;
const int SIZE = 100;
char name[SIZE];
cin>>n;

for(int i = 0; i < n; i++)
{
	cin>>name[i];
}

for(int i = 0; i < n; i++)
{
	if(name[i] == 'x' && name[i+1] == 'x' && name[i+2] == 'x') count++;
}

cout<<count<<endl;
return 0;
}

#include <iostream>
#include <cstring>
#include <cmath>

#include <vector>
#include <stack>
#include <queue>
#include <map>
#include <set>

#include <algorithm>
#include <functional>

#define N 300000 + 5 /* 3e5 +  5 */

#define pii pair<int, int>

#define piii pair<int, pair<int, int> >

using namespace std;

typedef long long ll;

int dx[] = { 0, 0, -1, 1 };
int dy[] = { -1, 1, 0, 0 };

// ll n, k, ary[N], sum[N];

int n;

string s;

int main(void)
{
	ios::sync_with_stdio(false);
	cin.tie(NULL);

	cin >> n >> s;

	int len = 1;

	vector<int> v;

	for (int i = 0; i < n; ++i) {
		while (i < n && s[i] == 'x' && s[i + 1] == 'x') {
			++len;
			++i;
		}
		v.emplace_back(len);
		len = 1;
	}

	int ans = 0;

	for (auto x : v) {
		if (x >= 3) {
			ans += (x - 2);
		}
	}

	cout << ans;

	return 0;
}

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define debug(n) cout << "DEBUG1 " << n << "\n";
#define debug2(n, m) cout << "DEBUG2 " << n << ' ' << m << "\n";
#define debug3(n, m, x) cout << "DEBUG3 " << n << ' ' << m << ' ' << x << "\n";
#pragma GCC optimize("O3")
using namespace std;
long long int mod(long long int b, long long int p, long long int m) {
    if (p == 0) return 1;
    else if (p % 2 == 0) return (mod(b, p / 2, m) * mod(b, p / 2, m)) % m; // a^(p/2) * a^(p/2) = a^p
    else if (p % 2 == 1) return (mod(b, (p - 1) / 2, m) * mod(b, (p - 1) / 2, m) * b) % m;
    else return 0; // a function must return something
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int n;
    cin >> n;
    char c;
    int cnt = 0;
    int sum = 0;
    for (int i = 0;i < n;i++) {
    	cin >> c;
    	if (c == 'x') {
    		cnt++;
		} else {
			if (cnt >= 3) sum += cnt - 2;
			cnt = 0;
		}
	}
	if (cnt >= 3) sum += cnt - 2;
	cout << sum << endl;
}

#include <iostream>
#include <string>
#include <vector>
using namespace std;

int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	s = "xxx" + string("$") + s;
	vector<int> z;
	z.resize(s.length());
	z[0] = 0;
	int c = 0;
	for (int i = 1; i < s.length(); i++)
	{
		while (i < s.length() && s[z[i]] == s[z[i] + i])
			z[i]++;
		if (z[i] == 3)
			c++;
	}
	cout << c;
}

#include <bits/stdc++.h>
using namespace std;
int l, ans;
string s;
int main() {
    cin >> l >> s;
    for (int i = 0, cnt = 0; i < l; ++i) {
        if (s[i] == 'x') {
            ++cnt;
            if (cnt == 3) {
                while (s[i] == 'x') {
                    s[i] = '0';
                    ++i;
                    ++ans;
                }
                cnt = 0;
            }
        } else {
            cnt = 0;
        }
    }
    cout << ans << endl;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
string s;
int n,cnt,ans;

int main()
{
//	freopen("cf987b.in","r"stdin);
//	freopen("cf978b.out","w",stdout);

	scanf("%d",&n);
	cin>>s;
	for(int i=0; i<n; i++)
	{
		if(s[i]=='x')
		{
			if(cnt==2)
			ans++;
			else cnt++;
		}
		else cnt = 0;
	}
	printf("%d",ans);
	return 0;
}

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int n,Count=0;
    scanf("%d",&n);
    char s[n];
    scanf("%s",&s);
    for(int i=0; i<n-2; i++){
        if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x') Count++;
    }
    printf("%d\n",Count);
    return  0;
}

#include <iostream>
#include <vector>
#include <cstdio>
#include <string>

#define pb push_back
#define mp make_pair
#define fr first
#define sc second
#define MOD 1000000007
#define len(x) x.size()
#define min3(a, b, c) min(a, min(b, c))
#define max3(a, b, c) max(a, max(b, c))
#define all(v) v.begin(), v.end()
#define alla(a,n) a, a + n

using namespace std;

using std::cout;
using std::cin;
using std::vector;
using std::pair;
using std::string;
using std::ios_base;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pll> vpll;
typedef vector<vll> vvll;
typedef vector<string> vs;

int32_t main()
{
	#ifndef ONLINE_JUDGE
		freopen("input.txt", "r", stdin);
		freopen("output.txt", "w", stdout);
	#endif

	ios_base::sync_with_stdio(false);
	cin.tie(NULL); cout.tie(NULL);

	int N;
	cin >> N;

	string message;
	cin >> message;

	int num_removals = 0;

	int num_x = 0;

	for (int i = 0; i < N; i++)
	{
		if (message[i] != 'x')
			num_x = 0;
		else
		{
			if (num_x <= 2)
				num_x++;
			if (num_x >= 3)
				num_removals++;
		}
	}
//	bool other_found = false;
	//for (int i = 0; i < N; i++)
	//{
	//	if (message[i] != 'x')
	//	{
//	//		other_found = true;

	//		if (num_x >= 3)
	//			num_removals += num_x - 2;
	//		num_x = 0;
	//	}
	//	else
	//		num_x++;
	//}

	//if (num_x >= 3)
	//	num_removals += num_x - 2;
//	if (!other_found)
//		num_removals += num_x - 2;
	cout << num_removals << "\n";
	return 0;
}

#include <iostream>
#include <string>

   using namespace std;

int main() {
	int n, k, sum;
	bool flag = false;
	string s;
	cin >> n >> s;
	s += " ";
	k = sum = 0;
	for (int i = 0; i < n; i++) {
		if (i + 1 < n && (s[i] == 'x') && (s[i+1] == s[i])) {
			k++;
		} else {
			if (k >= 0) {
				++k;
				if (k >= 3) {
					sum += (k - 2);
					flag = true;
				}
			}
			k = 0;
		}
	}
	if (flag) {
	    cout << sum << "\n";
	} else {
		cout << 0 << "\n";
	}
return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n;
    cin>>n;
    string s;
    cin>>s;
    int d=0;
    while(s.find("xxx",0)!=-1)
    {
        s.erase(s.find("xxx",0),1);
        d++;
    }
    cout<<d;
    return 0;
}

#include<conio.h>
#include<locale>
#include<iostream>
#include<vector>
#include<string>
#include<cmath>
#include<algorithm>
using namespace std;
int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	int count = 0, count1 = 0, label = 0;
	for (int i = 0; i < s.length(); i++)
	{
		while (s[i] == 'x')
		{
			count++;
			i++;
			label = 1;
		}
		if ((count >= 3)&&(label==1))
		{
			count1 += (count - 2);
		}
		label = 0;
		count = 0;
	}
	cout << count1;
	//_getch();
}

#include <iostream>
using namespace std;

int main()
{
    int n,c=0,ans=0,j;cin>>n;
    char a[n+1];cin>>a;
    for(int i=0;i<n;i=i+c)
    {
        c=0;
        if(a[i]=='x')
        {
            j=i;
            while(a[j]=='x' && j<n)
            {
                c++;j++;
            }
            if(c>=3)ans=ans+(c-2);
        }
        if(c==0)c=1;
    }
    cout<<ans;
}

#include <bits/stdc++.h>

#define inf 0x3f3f3f3f

#define INF 0x3f3f3f3f3f3f3f3fLL

#define mod 1000000007

#define hmod 911382323

#define pb push_back

#define sq(x) ((x)*(x))

#define sz(a) ((int)a.size())

#define LEN(a) (a.length())

#define x first

#define y second

#define ls (u<<1)

#define rs (ls + 1)

#define mid (st + ed >> 1)

#define eps 1e-8

#define bpt(x) (__builtin_popcount(x))

#define bptl(x) (__builtin_popcountll(x))

#define bit(x, y) (((x)>>(y))&1)

#define bclz(x) (__builtin_clz(x))

#define bclzl(x) (__builtin_clzll(x))

#define bctz(x) (__builtin_ctz(x))

#define bctzl(x) (__builtin_ctzll(x))

#define rands(n) (rand()%n+1)

#define rand0(n) (rands(n)-1)

#define Rands(n) ((INT)rand()*rand()%n+1)

#define Rand0(n) (Rands(n)-1)

#define PQ priority_queue<pii, vector<pii>, greater<pii> >

#define rep(i, a, b) for(int i=a; i<b; i++)

#define eprintf(...) fprintf(stderr, __VA_ARGS__)

#define shit(a) (1 << (a))

#define all(a) ((a).begin(), (a).end())

#define rev(a) (power(a, mod-2, mod))

#define add_edge(u, v) {nxt[E]=head[u];to[E]=v;head[u]=E++;}

#define init_edge(n) {memset(head, -1, sizeof head);E=0;}

#define input_tree {int n;cin>>n;init_edge(n); for(int i=0, u, v; i<n-1; i++) {gn(u); gn(v); add_edge(u,v); add_edge(v,u);}}

#define ADD(u, v) {u+=v;u%=mod;}

using namespace std;

typedef long long INT;

typedef unsigned long long UINT;

typedef unsigned int uint;

typedef complex<double> Complex;

typedef double DO;

typedef vector<int> VI;

typedef pair<int, int> pii;

typedef pair<INT, INT> PII;

typedef pair<pii, int> ppi;

typedef pair<int, pii> pip;

typedef pair<DO, DO> pdd;

typedef pair<int, DO> pid;

typedef pair<DO, int> pdi;

template<typename T, typename U> inline void smin(T &a, U b) {if (a>b) a=b;}

template<typename T, typename U> inline void smax(T &a, U b) {if (a<b) a=b;}

template<class T>inline void gn(T &x) {char c, sg=0; while (c=getchar(), (c>'9' || c<'0') && c!='-');for((c=='-'?sg=1, c=getchar():0), x=0; c>='0' && c<='9'; c=getchar()) x=(x<<1)+(x<<3)+c-'0';if (sg) x=-x;}

template<class T>inline void print(T x) {if (x<0) {putchar('-');return print(-x);}if (x<10) {putchar('0'+x);return;} print(x/10);putchar(x%10+'0');}

template<class T, class T1>inline void gn(T &x, T1 &y) {gn(x); gn(y);}

template<class T, class T1, class T2>inline void gn(T &x, T1 &y, T2 &z) {gn(x); gn(y); gn(z);}

int power(int a, int b, int m, int ans=1) {

	for (; b; b>>=1, a=1LL*a*a%m) if (b&1) ans=1LL*ans*a%m;

	return ans;

}

inline uint myrand(int n) {

	uint u = rand()%n;

	int c = rand()%10;

	u ^= u << c;

	u^=(u<<7)&263692864;

	u^=(u<<15)&402273075;

	u%=n;

	return u;

}

char s[111];

int main() {

#ifndef ONLINE_JUDGE

	freopen("in.in", "r", stdin);

	freopen("out.out", "w", stdout);

	int _time=clock();

#endif

	int ans=0;

	int n;

	cin >> n;

	scanf("%s", s);

	int cnt=0;

	for(int i=0; i<n; i++) {

		if(s[i] == 'x') cnt++;

		else cnt=0;

		if(cnt>=3) ans++;

	}

	cout << ans << endl;

#ifndef ONLINE_JUDGE

	cerr<<"The running time is : " << (DO)(clock()-_time) / CLOCKS_PER_SEC<<endl;

#endif

	return 0;

}

#include <bits/stdc++.h>

using namespace std;

char s[110];

int main() {

#ifndef ONLINE_JUDGE

	freopen("in.in", "r", stdin);

	freopen("out.out", "w", stdout);

#endif

	int n;

	scanf("%d",&n);

	scanf("%s",s);

	int sum=0;

	int num=0;

	for(int i=0;i<=n;i++){

		if(s[i]=='x') sum++;

		else {

			if(sum>2) num+=(sum-2);

			sum=0;

		}

	}

	printf("%d",num);

	return 0;

}

#include<bits/stdc++.h>

#define x first

#define y second

#define eps 1e-7

#define pb push_back

#define inf 0x3f3f3f3f

#define mod 1000000007

#define sq(x) ((x)*(x))

#define cb(x) ((x)*(x)*(x))

#define bit(x, y) (((x)>>(y))&1)

#define bctz(x) (__builtin_ctz(x))

#define bclz(x) (__builtin_clz(x))

#define bclzl(x) (__builtin_clzl(x))

#define bctzl(x) (__builtin_ctzl(x))

#define bpt(x) (__builtin_popcount(x))

#define bptl(x) (__builtin_popcountll(x))

#define pi 3.1415926535897932384626433832795

#define PQ priority_queue<pii, vector<pii>, greater<pii> >

using namespace std;

typedef double DO;

typedef long long INT;

typedef vector<int> VI;

typedef pair<int, int> pii;

typedef pair<pii, int> pi3;

template<typename T, typename U> inline void smin(T &a, U b) {if(a>b) a=b;}

template<typename T, typename U> inline void smax(T &a, U b) {if(a<b) a=b;}

template <class T> inline void gn(T &x) {char c, sg=0; while(c=getchar(), (c>'9' || c<'0') && c!='-'); for((c=='-' ? sg=1, c=getchar() : 0), x=0; c>='0' && c<='9'; c=getchar()) x=(x<<1)+(x<<3)+c-'0'; if(sg) x=-x;}

template <class T1, class T2> inline void gn(T1 &x1, T2 &x2) {gn(x1), gn(x2);}

template <class T1, class T2, class T3> inline void gn(T1 &x1, T2 &x2, T3 &x3) {gn(x1, x2), gn(x3);}

template <class T1, class T2, class T3, class T4> inline void gn(T1 &x1, T2 &x2, T3 &x3, T4 &x4) {gn(x1, x2), gn(x3, x4);}

template <class T> inline void print(T x) {if(x<0) {putchar('-'); return print(-x);} if(x<10) {putchar('0'+x); return ;} print(x/10); putchar(x%10+'0');}

template <class T> inline void println(T x) {print(x); putchar('\n');}

template <class T> inline void printsp(T x) {print(x); putchar(' ');}

template <class T1, class T2> inline void print(T1 x1, T2 x2) {printsp(x1), println(x2);}

template <class T1, class T2, class T3> inline void print(T1 x1, T2 x2, T3 x3) {printsp(x1), printsp(x2), println(x3);}

template <class T1, class T2, class T3, class T4> inline void print(T1 x1, T2 x2, T3 x3, T4 x4) {printsp(x1), printsp(x2), printsp(x3), println(x4);}

int power(int a, int b, int m, int ans=1) {

	for(; b; b>>=1, a=1LL*a*a%m) if(b&1) ans=1LL*ans*a%m;

	return ans;

}

#define NN 110

char s[NN];

int main() {

#ifndef	ONLINE_JUDGE

	freopen("in.in", "r", stdin);

	freopen("out.out", "w", stdout);

#endif

	int n;

	scanf("%d %s", &n, s);

	int ans=0;

	for(int i=0, j=0; i<n; i=j) {

		for(j=i+1; j<n && s[i]==s[j]; j++) ;

		if(s[i]=='x' && j-i>2) ans+=j-i-2;

	}

	println(ans);

}

#include<iostream>
#include<stack>
#include<deque>
#include<queue>
#include<algorithm>
#include<cmath>
#include<vector>
#include<map>
#include<string>
#include<set>
using namespace std;
int main()
{
	int x, c = 0;
	cin >> x;
	string s;
	cin >> s;
	while (s.find("xxx")<s.size())
	{
		c++;
		s.erase(s.find("xxx"), 1);
	}
	cout << c << "\n";
}

#include<bits/stdc++.h>
using namespace std;
//Int data type
#define sc1(a)              scanf("%d", &a)
#define sc2(a, b)           scanf("%d %d", &a, &b)
#define sc3(a, b, c)        scanf("%d %d %d", &a, &b, &c)
#define sc4(a, b, c, d)     scanf("%d %d %d %d", &a, &b, &c, &d)

int main()
{
    int n,m,i,j,a,b,ck=0;
    sc1(n);
    string arr;
    cin>>arr;
    for(i=0; i<n; i++){
        if(arr.compare(i, 3, "xxx")==0)
            ck++;
    }
    cout<<ck<<endl;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
  int n, cnt=0 ,tot=0; string x;
  cin>>n; cin>>x;
  for(int i=0 ; i<n ; i++)
  {
      if(x[i]=='x')
      {
          cnt++;

      }
      else
        {

      cnt=0;
        }
        if(cnt>2)
            {tot+=cnt-2; cnt-=(cnt-2);}
  }

  cout<<tot;

    return 0;
}

#include <iostream>
#include <vector>
using namespace std;

int main () {

    int n, count = 0, ans = 0;
    string in;
    cin >> n >> in;

    for (int i = 0; i < in.size(); i++) {
        if (in[i] == 'x') {
            count++;
        } else {
            if (count > 2)
                ans += count - 2;
            count = 0;
        }
    }
    if (in[in.size() - 1] == 'x')
        if (count > 2)
            ans += count - 2;

    cout << ans << endl;

    return 0;
}

#include<iostream>
#include<string>
using namespace std;
int main(){
string s;
int b,n;
cin>>b>>s;
for(int i=0;i<s.size();i++)
if(s[i]=='x'&&s[i+1]=='x'&&s[i+2]=='x')
{n++;}
cout<<n;
     }

#include <string>
#include <vector>
#include <algorithm>
#include <iostream>
#include <bits/stdc++.h>
#define lli long long int
#define li long int
#define ld long double
using namespace std;

int main() {
    int n,cnt=0;
    string s;
    cin>>n>>s;
    for(int i=0;i<=n-3;i++){
        if(s.substr(i,3)=="xxx") cnt++;
    }
    cout<<cnt<<endl;

}

#include<stdio.h>
#include<string.h>
int main(){

 int i,j,count=0,n,count1=0;
 char str[1000];
 scanf("%d",&n);
 scanf("%s",str);

 for(i=0;i<n;i++){// printf("count = %d\n",count);
    //if(str[i]=='x'){
      //  count++;
    //}
    if(str[i-1]=='x' && str[i]=='x' && str[i+1]=='x'){
        count1++;
    }
 }
 //printf("%d\n",count);
 //printf("%d\n",count1);

 //count=count-count1;

 printf("%d\n",count1);

 return 0;
}

#include <iostream>

int main()
{
	int n, num = 0;
	char* str;

	std::cin >> n;

	str = new char[n];

	int counter = 0;
	for (int i = 0; i < n; i++)
	{
		std::cin >> str[i];

		if (str[i] == 'x')
			counter++;
		else
			counter = 0;

		if (counter > 2)
			num++;
	}

	delete[] str;

	std::cout << num;

	return 0;
}

/* Coder: @SumitRaut
 * Date: 05-09-2020 10:38:26
 */
#include <bits/stdc++.h>
#define debug1(x) cout<<#x<<' '<<x<<'\n'
#define debug2(x,y) cout<<#x<<' '<<x<<' '<<#y<<' '<<y<<'\n'
#define debug3(x,y,z) cout<<#x<<' '<<x<<' '<<#y<<' '<<y<<' '<<#z<<' '<<z<<'\n'
#define ll long long
#define speedup ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
using namespace std;

void solve() {
    int n;
    cin>>n;
    string str;
    cin>>str;
    int ans=0,c=0;
    for(auto &it:str) {
        if(it=='x') ++c;
        else ans+=max(0,c-2),c=0;
    }
    ans+=max(0,c-2);
    cout<<ans<<'\n';
}
int main()
{
    speedup;
    // int t; cin>>t; while(t--)
    solve();
    return 0;
}

#include<stdio.h>
#include <string.h>
#include <algorithm>
using namespace std;
char s[105];
int main()
{
    int n;
    scanf("%d", &n);
    getchar();
    scanf("%s", s);
    int ans = 0, x = 0;
    for(int i = 0; i < n; i++)
    {
        //printf("%c", s[i]);
        if(s[i] != s[i - 1] && i)
        {
            //printf("%d ", x);
            if(x >= 3)
                ans += (x - 2);
            x = 0;
        }
        if(s[i] == 'x')
        {
            x++;
        }
    }
    //printf("%d", x);
    if(x >= 3)
        ans += (x - 2);
    printf("%d", ans);
    return 0;
}
//2019-07-21 19:34:04.036

#include <bits/stdc++.h>

using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n ; cin >> n;
	string s ; cin >> s;

	int total = 0 , NumberOfX = 0 ;

	char PrevChar = ' ';
	for (int i = 0 ; i < n ; i++)
    {
        if (s[i] == 'x')
        {
            if (NumberOfX >= 2)
                ++total;
            else
                ++NumberOfX;
        }else
            NumberOfX = 0;
    }

    cout << total ;

    return 0;
}

#include <iostream>

using namespace std;

int main() {

  int n,cnt,tmp;
  tmp=2;
  cin>>n;
  cnt=0;
  string s;
  cin>>s;
  bool flag=0;
  for(int i=0;i<n;i++)
  {
    if(s[i]!='x') {tmp=2;}
    else
    {
      if(tmp>0) {cnt--; tmp--;}
      cnt++;
    }

  }

  cout<<cnt;

  return 0;
}

// Example program
#include <iostream>
#include <string>
using namespace std;
int main()
{
string x,j;
int n,f=0,l=0;
cin>>n;
cin>>j;
for (int d=0; d<n;d++)
if (j[d]=='x')
f++;
else {
    if (f>=3)
    l=l+f-3+1;
    f=0;

}
if(f>=3)
l=l+f-3+1;
    cout<<l;
}

#include<bits/stdc++.h>
using namespace std;

char ch[110];

int main()
{
	int n;
	scanf("%d",&n);
	for(int i=1;i<=n;i++) cin>>ch[i];
	int cnt=0;
	for(int i=1;i<=n-2;i++)
	{
		if(ch[i]=='x'&&ch[i+1]=='x'&&ch[i+2]=='x') cnt++;
	}
	printf("%d\n",cnt);
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	int cnt = 0;
	int tot = 0;
	for(int i = 0; i < n; i++)
	{
		if(s[i] == 'x'){
			cnt++;
		}else{
			if(cnt > 2){
				tot += (cnt - 2);
			}
			cnt = 0;
		}
	}
	if(cnt == n){
		cout << cnt - 2  << "\n";
	}else if(cnt > 2){
		cout << tot + (cnt-2) << endl;
	}else {
		cout << tot << endl;
	}
	return 0;
}

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <queue>

using namespace std;
int main()
{
    int n;
    cin >> n;
    string arr;
    cin >> arr;
    int len=arr.length();
    int t=0;
    for(int i=0; i<len; i++)
    {
        int m=1;
        for(int j=i+1; j<len; j++)
            if(arr[i]=='x'&&arr[i]==arr[j])
            {
                m++;
                if(m>=3)
                {
                    t++;
                    break;
                }
            }
            else
                break;
    }
    printf("%d\n", t);
    return 0;
}

#include <stdio.h>
#include <iostream>
#include <string>
using namespace std;
 int main(){
 	int size;
 	cin >> size;
 	string word;
 	cin >> word;
 	int total = 0;
 	const char *arr = word.c_str();
 	char last = arr[0];
 	int count = 0;
	for (int i = 0; i < size; ++i){
		if(last == arr[i] && last == 'x'){
			count++;
			if(count==3){
				count--;
				total++;
			}
		}else{
			count = 1;
		}
		last = arr[i];
	}
	cout << total << endl;
 	return 0;
 }

#include<bits/stdc++.h>
using namespace std;

int main(){

    int num;
    cin >> num;
    int cont = 0;
    string cad;
    cin >> cad;
     int cont_res = 0;
     int res = 0;
    for( int i = 0; i < num; i++){
        if(cad [i] == 'x' && cad[i+1] == 'x' && cad[i+2] == 'x'){
            cont++;
            //cout << cad[i] << " " << cad[i+2] << " cont = " << cont<< endl;
            if (cont >1){
                res = cont;
            }else{
                res = 1;
            }
        }
    }

    //int res = 0;
    if(cad[0] == 'x' && cad[2] != 'x'){
        cout << 0 << endl;
    }else{
        cout << res << endl;
    }
}

#include <iostream>
#include <map>
#include <string>
#include <vector>
#include <cstdlib>
#include <algorithm>

using namespace std;

int main()
{
    int n,cont = 0,total = 0;cin>>n;
    string a;cin>>a;
    for(int i = 0;i < n-1;i++)
    {
        if(a[i] == 'x' && a[i+1]=='x')
        {
            cont++;
            if(i+1 ==n-1)
                total+=cont-1;
        }
        else if(a[i] == 'x' && a[i+1] !='x')
        {
            cont++;
            if(cont > 1)
            {
                total+=(cont-2);
            }
            cont = 0;
        }

    }
    cout<<total;
}

#include<iostream>
#include<algorithm>
using namespace std;
int main()
{
	int n;
	int i, j, k;
	char a[105];
	int countn1, countn2;
	while (cin >> n)
	{
		for (i = 0; i < n; i++) cin >> a[i];
		countn1 = 0, countn2 = 0;
		for (i = 0; i < n; i++)
		{
			if (a[i] == 'x') countn1++;
			else countn1 = 0;
			if (countn1 >= 3) countn2++;
		}
		cout << countn2 << endl;
	}
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
string n;
long long ans,a;
int main(){
	cin>>a>>n;
	while(n.find("xxx")!=-1){
		n.erase(n.find("xxx"),1);
		ans++;
	}
	cout<<ans<<endl;
}

#include <iostream>
#include <cstdio>
using namespace std;
typedef long long ll;
/*inline char gc(){
	static char buf[1<<14],*p1=buf,*p2=buf;
	return p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<14,stdin),p1==p2)?EOF:*p1++;
}*/
#define dd c=getchar()
inline ll read(){
	ll x=0,f=1;char dd;
	for(;!isdigit(c);dd){if(c=='-')f=-1;if(c==EOF)return EOF;}
	for(;isdigit(c);dd)x=(x<<1)+(x<<3)+(c^48);return x*f;
}
#undef dd
inline void write(ll x){
	if(x<0)putchar('-'),x=-x;
	if(x>9)write(x/10);putchar(x%10|48);
}
const ll N=100;
ll n,tot,ans;char a;
int main(){
	for (ll n=read();n;--n){
		cin>>a;
		if (a=='x') ++tot;else tot=0;
		if (tot>2) tot=2,++ans;
	}write(ans);
	return 0;
}

#include <iostream>
using namespace std;
int n, c, s;
string a;
int main() {
	cin>>n>>a;
	for(int i=0; i<n; i++)
	a[i]=='x' ? s += (++c>2) : c = 0;
	cout<<s;
}

#include <bits/stdc++.h>

#define MAX ((int)51)
#define INF ((int)1000000000)
#define MOD ((ll)1000000007)
#define EPS ((double)1e-8)
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define mod(x) ((x) % MOD)
#define modS(x) ((((x) % MOD) + MOD) % MOD)
#define DAD(x) ((x) >> 1)
#define LEFT(x) ((x) << 1)
#define RIGHT(x) ((x) << 1 | 1)
#define popcount __builtin_popcount
#define clz __builtin_clz
#define ctz __builtin_ctz
#define gcd __gcd
#define endl '\n'

using namespace std;

typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    //freopen("01.in", "r", stdin);
    //freopen("01.out", "w", stdout);
    string ss = "jose\
                 ariel\
                 romero,\
                 esto\
                 es\
                 una\
                 prueba";
    int n, ans = 0;
    string s;
    cin >> n >> s;
    for(int i = 2 ; i < n ; i++)
        if(s[ i ] == 'x' && s[ i - 1 ] == 'x' && s[ i - 2 ] == 'x')
            ans++;
    cout << ans << endl;

    int asdf=13;

    return 0;
}

#include<iostream>
#include<string.h>
#include<string>
using namespace std;
int main(){
	int n,i,x=0,j,y;
	cin>>n;
	char a[101];
	for(i=0;i<n;++i){
		cin>>a[i];
	}
	i=0;
	while(i<n){

		if(a[i]=='x'){
			y=1;
			for(j=i+1;j<n;++j){
				if(a[j]=='x'){
					++y;
					i=j;
				}
				if(a[j]!='x') break;
			}
			if(y>=3) x=x+y-2;
		}
		++i;
	}
	cout<<x;
	return 0;
}

#include<bits/stdc++.h>

using namespace std;

int main(){
    int n;
    cin >> n;
    int currlen =0; char c; int res=0;
    for(int i=0; i<n; i++){
        cin >> c;
        if(c=='x')
            currlen++;
        else
            res += max(currlen-2, 0), currlen=0;
    }
    res+= max(currlen-2, 0);
    cout<<res<<endl;
}

#include<iostream>

using namespace std;

int main(){
    int n;
    string s;
    cin >> n >> s;
    int len = 0;
    int count = 0;
    for (int i = 0; i < n-2; i++){
        if (s[i] =='x' && s[i+1]=='x' && s[i+2]=='x'){
            count++;
        }
    }
    cout << count << endl;

    return 0;
}

//FIle name

#include<iostream>
#include<string>
using namespace std;

int main(){

	char s[100];

	int n;
	int cnt=0;

	cin>>n;
	cin>>s;

	for(int i=0;i<n-2;i++){

		if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x' )
		cnt++;

	}

	cout<<cnt<<endl;

}

#include<stdio.h>
using namespace std;
int main()
{
    char str[1005];
    int n;
    scanf("%d",&n);
    scanf("%s",str);
    int ans=0;
    for(int i=0;i+2<n;i++)
    {
        if(str[i]=='x'&&str[i+1]=='x'&&str[i+2]=='x')
            ans++;
    }
    printf("%d\n",ans);
    return 0;
}
//2019-07-21 19:08:07.387

#include <iostream>
using namespace std;
int main(){
int n, k=0;
string s,q="xxx";
cin>>n>>s;
int i=0;
while(true){
	if(s.length()<3) {cout<<k; return 0;}
	if(s.substr(i,3)==q) { k++; if(s.length()==3) {cout<<k; return 0;}
	s.erase(0,i+3);
	for(int j = 0;j < s.length();j++){
		if(s[j]=='x') {k++; if(j==s.length()-1){cout<<k; return 0;	} 	}
		else {s.erase(0,j+1); j=s.length(); i=-1;}
			}
		}
	i++;
	if(i==s.length()-1){cout<<k; return 0;	}
	}
cout<<k;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
	int n;
	cin >> n;
	n = 0;
	string S;
	cin >> S;
	for (int i = 0; S[i + 2] != '\0'; i++)
	{
		if (S[i] == 'x' &&S[i + 1] == 'x' &&S[i + 2] == 'x')
			n++;
	}
	cout << n;
	return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main() {
	int out = 0;
	int n;
	int count = 0;
	char *arr;

	scanf("%d", &n);
	arr = (char*)malloc(sizeof(char)*(n + 1));
	scanf("%s", arr);

	for (int i = 0;i < n - 2;) {
		count = 0;
		if (arr[i] == 'x' && arr[i + 1] == 'x' && arr[i + 2] == 'x') {
			for (int j = i + 2;j < n;j++) {
				if (arr[j] == 'x') {
					count++;
					out++;
				}
				else break;
			}
		}
		if (count != 0) i = i + count + 2;
		else i++;
	}

	printf("%d", out);
}

#include<bits/stdc++.h>
using namespace std;
int n,s;
char a[105];
void sc (int x){
	for (int i=x;i<=n;i++) a[i]=a[i+1];
	n--;
}
int main (){
    scanf ("%d",&n);
    scanf ("%s",a+1);
    for (int i=1;i<=n;i++){
    	if (a[i]=='x'&&a[i+1]=='x'&&a[i+2]=='x') sc(i),i--,s++;
    }
    printf ("%d",s);
    return 0;
}

#include<iostream>
#include<algorithm>
#include<string>
#include<stdio.h>
#include<string.h>
using namespace std;
int main() {
	int n;char a[120];
	cin >> n; int ans = 0;
	for (int i = 0; i < n; i++)
	{
		cin >> a[i];
	}
	for (int i = 0; i < n-2; i++)
	{
		if (a[i] == 'x'&&a[i + 1] == 'x'&&a[i + 2] == 'x')
			ans++;
	}
	cout << ans << endl;
}

#include<bits/stdc++.h>
using namespace std;
int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int n ;
	cin >> n;
	string s;
	cin >> s;
	int ans = 0;
	int ct = 0;
	long int i;
	for( i = 0;i < n; i++){
		if(s[i] == 'x')
		   ct++;
		else
		{
		 ans += max(0, ct - 2);
		 ct = 0;
		}
	}
	ans += max(0, ct - 2);
	cout << ans;

}

#include <iostream>
#include <string>
using namespace std;

int main() {
	int n,i=0,p=0,m=0;
	string s;
	cin>>n>>s;
	while (n--) {
	    if (s[i]=='x') {m++; i++;}
	    else if (m>2) {p+=m-2; m=0; i++;}
	        else {m=0; i++;}
	    if (!n && m>2) p+=m-2;

	}

	cout<<p;
}

#include<iostream>
using namespace std;
int main()
{
    int n,i=0,j=0,v=0,c=0;
    cin>>n;
    char s[200];
    for(i=0;i<n;i++)
     cin>>s[i];
    for(i=0;i<n;i++)
    {
        if(s[i]=='x')
            c=c+1;
        else
            {if(c>2)
              v=v+c-2;
              c=0;

            }
    }
    if(c>2)
    v=v+c-2;
    cout<<v;
}

#include<bits/stdc++.h>
using namespace std;
int a,c,d,e;
char b[101];
int main()
{
	cin>>a>>b;
	for(;c<a;c++)
	{
		d=(b[c]==120)?d+1:0;
		if(d>2)
		{
			e++;
		}
	}
	cout<<e;
	return 0;
}

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
using namespace std;
int sum,len,ans;
char ch,s[105];
int main()
{
    cin>>len>>s;
    ch=s[0];
    for (int i=0;i<len;i++)
        if (ch==s[i]&&ch=='x')
        {
            sum++;
            if (sum>=3)
                ans++;
        }
        else
        {
            ch=s[i];
            sum=1;
        }
    cout<<ans;
    return 0;
}

#include<bits/stdc++.h>
#define yoo long long int
using namespace std;
int main()
{
	int n;
	cin>>n;
	string s;
	cin>>s;
	int c=0;
	for(int i=0;i<s.size();i++)
	{
		if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x')
		{
			c++;
		}
	}
	cout<<c<<endl;
}

#include<bits/stdc++.h>
using namespace std;
string n;
long long ans,a;
int main()
{
    cin>>a>>n;
    while(n.find("xxx")!=-1)
    {
        n.erase(n.find("xxx"),1);
        ans++;
    }
    cout<<ans;
}

#include <iostream>
#include<bits/stdc++.h>
using namespace std;

int main() {
	// your code goes here
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n,c=0,cm=0;
	cin>>n;
	string s;
	cin>>s;
	for(int i=0;i<n;i++)
	{
		if(s[i]=='x')
		c++;
;
		if(s[i]!='x')
		c=0;
		if(c>=3)
		{
			cm=cm+1;

		}
		cout<<i<<'n'<<c<<'n'<<cm<<'n';
	}
	cout<<cm;
	return 0;
}

#include<bits/stdc++.h>

using namespace std;

int main(){
	int n, i, j, x, r;
	char c;
	scanf("%d", &n);
	x = r = 0;
	for(i = 0; i < n; i ++){
		scanf(" %c", &c);
		if(c == 'x')
			x ++;
		else if(x >= 3){
			r += x - 2;
			x = 0;
		}
	}
	if(x >= 3)
		r += x - 2;
	printf("%d\n", r);
	return(0);
}

#include <iostream>
#include <map>
#include <set>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <unordered_set>
#define elif else if
typedef short int si;
typedef unsigned short int usi;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
using namespace std;
int main() {
    ll n;
    cin>>n;
    ll ans = 0, now = 0;
    for (ll i=0; i<n; ++i){
        char temp;
        cin>>temp;
        if (temp=='x')
            ++now;
        else{
            ans+=max(ll(0),now-2);
            now=0;
        }
    }
    cout<<ans;
    return 0;
}

#include <iostream>
#include <string>
#include <algorithm>
#include <iterator>

using namespace std;

int a, b, c, d, n, x, mas[100000];
string s, s1, s2, sas[100000];

int main()
{
	ios::sync_with_stdio(0);
	cin >> a;
	cin >> s;
	for (int i = 0; i < a; i++)
	{
		for (int k = 0; k < a; k++)
		{
			n = 0;
			if (s[k] == 'x')
				c++;
			if (s[k] != 'x')
				c = 0;
			if (c == 3)
			{
				n = 1;
				d = k;
				break;
			}
		}
		if (n == 1)
		{
			a--;
			s.erase(d, 1);
			x++;
		}
	}
	cout << x;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
    int x;
    cin>>x;
    string num;
    cin>>num;
    int c=0;
    for(int i=0;i<x;i++){
        if(i<x-4){
            if(num.substr(i,3)=="xxx"){
                c++;
            }
        }
    }
    cout<<c;
    return 0;
}

#include <iostream>
using namespace std;
int main() {
	int n, c, total=0;//total必须要初赋值，不然543836282
	string a;
	cin>>n>>a;
	for(int i=0;i<n;i++)
		a[i]=='x' ? total += (++c>2) : c = 0;
	//if(s[i]=='x' and s[i+1]=='x' and s[i+2]=='x') k++;
	//相当于不断判断是不是够三个
	cout<<total<<endl;
}

#include<bits/stdc++.h>
using namespace std;

int main(){

    int n,i, xc=0, xr=0; cin>>n;
    string x; cin>>x;

    for(i=0; i<n; i++){
        if(x[i]=='x'){
            xc++;
            if(xc==n)
                xr=xc-2;
        }else if(xc>=2 && xc!=n){
            xr=xc-2;
            xc=0;
        }
    }
    cout<<xr<<endl;
}

#include<stdio.h>
#include<string.h>
int main(){

 int i,j,count=0,n;
 char str[1000];
 scanf("%d",&n);
 scanf("%s",str);
 //printf("%s",str);

 //for(i=0;i<n;i++){// printf("count = %d\n",count);
   //     scanf("%c",str);
    //}

    //for(i=0;i<n;i++){// printf("count = %d\n",count);
    //printf("%c",str);
    //}

 for(i=0;i<n;i++){// printf("count = %d\n",count);
    if(str[i]=='x'){
        count++;
        //printf("count = %d\n",count);
    }
    if(str[i-1]=='x' && str[i]!='x' && count==2)
        count=0;
 }
 if(count==0)printf("0\n");
 else
 {
     count=count-2;
    printf("%d\n",count);
 }
return 0;
}

#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
#define pb push_back
#define inf INT_MAX
#define mk make_pair
#define MOD 1000000007
#define in insert
int main()
{
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    ll n;	cin>>n;
    string s;	cin>>s;
    ll cx=1,ans=0,f=0;
    for(ll i=0;i<n-1;i++)
    {
    	if(s[i]=='x' && s[i+1]=='x')
    	{
    		cx++;
		}
		else
		{
			f=1;
			if(cx>=3)
				ans+=cx-2;
			cx=1;
		}
	}
	if(cx>=3)
		ans+=cx-2;
	if(ans==0 && f==0)
	{
		cout<<cx-2<<endl;
	}
	else if(f==1)
	{
		cout<<ans<<endl;
	}
	else
		cout<<0<<endl;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n;
	string s;
	cin>>n>>s;
	int ans=0;
	for(int i=0;i<n-3;i++)
	{
		if(i+3<n && s[i]=='x' && s[i+1]=='x' && s[i+2]=='x')
		{
			ans+=1;
			i=i+3;
			int count=0;
			while(s[i]=='x')
			{
				i++;
				count++;
			}
			ans+=count;
			i--;
		}
	}
	cout<<ans<<endl;
}

#include<bits/stdc++.h>

using namespace std;

int main(){
	int n, i, j, x, r;
	char c;
	scanf("%d", &n);
	x = r = 0;
	for(i = 0; i < n; i ++){
		cin >> c;
		if(c == 'x')
			x ++;
		else if(x >= 3){
			r += x - 2;
			x = 0;
		}
	}
	if(x >= 3)
		r += x - 2;
	printf("%d\n", r);
	return(0);
}

#include<cstdio>
#include<iostream>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<utility>
#include<functional>
using namespace std;

int main()
{
	ios::sync_with_stdio(false);
	int n, res = 0;
	string s;
	cin >> n;
	cin >> s;
	int len = s.size(), ok = 0, cur ;
	for (int i = 2; i < len; i++)
	{
		if (s[i] == 'x' && s[i - 1] == 'x' && s[i - 2] == 'x')
		{
			ok = 1;
			cur = 1;
			continue;
		}
		if (s[i] == 'x' && ok)
			cur++;
		else if (s[i] != 'x'&& ok)
		{
			res += cur;
			ok = 0;
		}
	}
	cout << res << endl;
	return 0;
}

#include <iostream>
#include <cstdio>
#include <windows.h>
#include <cstring>

using namespace std;

typedef long long ll;
const int INF = 100005;
int n;
char a[105];
int t1 = 0,t2 = 0;
int main()
{
    cin >> n;
    for(int i = 0;i < n;i++)
    {
        cin >> a[i];
    }
    int t1 = 0,t2 = 0;
    if(a[0]=='x'&&a[1] == 'x'&&a[2] == 'x')
    {
        for(int i = 2;i < n;i++)
        {
            if(a[i] == 'x')
                t1++;
            else
                break;
        }
        for(int i = 2;i < n - 2;i++)
        {
            if(a[i - 1]!='x')
            {
                if(a[i] == 'x' && a[i+1] == 'x'&&a[i+2]=='x')
                {
                    for(int j = i+2;j < n;j++)
                    {
                        if(a[j] == 'x')
                            t1++;
                        else
                            break;
                    }
                    /*for(int j = i+2;j < n-2;j++)
                    {
                        if(a[j - 1]!='x')
                        {
                            if(a[j] == 'x' && a[j+1] == 'x'&& a[j+2] == 'x')
                                t2++;
                        }
                    }*/
                }
            }
        }
    }
    else
    {
        cout <<"0"<<endl;
        return 0;
    }
    cout << t1+t2 << endl;
    return 0;
}

#include<iostream>
#include<deque>
#include<string>
#include<algorithm>
#include<vector>
#include<map>
#include<stack>
#include<cmath>
#include<sstream>
#include<unordered_map>
#include<unordered_set>
#include<numeric>
#include<iomanip>
#include <ostream>
using namespace std;
#ifdef LOCAL
#else
#define FUNC(name) template <ostream& out = cout, class... T> void name(T&&...){ }
FUNC(prints) FUNC(printe) FUNC(printw) FUNC(printew) FUNC(printb) FUNC(printd) FUNC(printde);
#endif
template <class T>
istream& operator >> (istream& in, vector<T>& v){ for(auto& e : v){ in >> e; } return in; }
#define f(i,l,n) for(int i = l;i < n;i++)
#define f0(i,n) f(i,0,n)
#define pb push_back
#define pob pop_back
#define ci cin >>
#define co cout <<
int main(){
    int n = 0;
    int k;
    ci k;
    string s;
    ci s;

    for(int i = 0;i < k;i++){
        if(s[i] == 'x'){
            int b = 0;
            int l;
            for(int j = i;j < k;j++){
                if(s[j] == 'x'){
                    b++;
                    l = j;
                }
                else{
                    break;
                }
            }
            if(b >= 3){
                n = b - 2;
            }
            i = l;
        }

    }
    co n;
}

#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
//#include<utility>
using namespace std;
int main(){
        int n;
       cin>>n;
       string s;
       int c=1;
       cin>>s;
       for(int i=0;i<n-1;i++){
                 if(s[i]==s[i+1] && s[i]=='x')
                 c++;
                if(c>=3)
                break;
       }
          if(c>=3)
          cout<<c-2;
          else
          cout<<c;

          return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main () {

    ios_base :: sync_with_stdio (0);
    cin.tie (0); cout.tie (0);
//    freopen("input.txt" , "r" , stdin);
//    freopen("output.txt" , "w" , stdout);
    int n ;
    cin >> n;
    string s;
    cin >> s;
    int kol = 0 , ans = 0;
    for(int i = 0 ; i < n ; i++){
        if(s[i] == 'x' and i != n - 1)kol++;
        else{
            if(s[i] != 'x'){
                if(kol >= 3)ans += kol - 2 , kol = 0;
            }else
                if(kol >= 2)ans += kol - 1 , kol = 0;
        }

    }
    cout << ans << endl;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
string st;
int x,ans;
int main()
{
	cin>>x;
	x=0;
    cin>>st;
    for(int i=0;i<st.size();i++)
    {
    	if(st[i]=='x')x++;
    	  else ans+=x>2?x-2:0,x=0;
	}
	cout<<ans;
    return 0;
}

#include <iostream>

using namespace std;

int main()
{
        int n, x = 0, cnt = 0, y;
        string s;
        cin >> n >> s;

        for (int i = 0; i < n; i++)
        {
                if (s[i] == 'x')
                {
                        for (int j = i; j < n; j++)
                        {
                                if (s[i] == s[j])
                                {
                                        cnt++;
                                        if (j == n-1)
                                        {
                                                y = 1;
                                                break;
                                        }
                                }

                                else
                                {
                                        i = j;
                                        break;
                                }
                        }

                        if (cnt >= 3)
                                x += cnt - 2;
                        cnt = 0;
                }

                if (y == 1)
                        break;
        }

        cout << x;
}

#include<iostream>
#include<algorithm>
#include<vector>
#include<cmath>
#include<cstring>
#include<numeric>
#include<climits>
#include<string>
#include<map>
#include<unordered_map>
#include<stack>
#include<set>
#include<unordered_set>

const long long MAX = 1000001;
const int mod = 1e9+7;
const double pi1 = acos(-1.0);
#define pi2 3.14159265358979323846264338327950
#define ll long long
#define pb push_back
#define f first
#define s second
#define all(x) (x).begin(), (x).end()
#define ub(x,k) ((upper_bound(all(x),k)) - ((x).begin()))
#define lb(x,k) ((lower_bound(all(x),k)) - ((x).begin()))
#define pii pair<int, int>

using namespace std;

ll binpow(ll a, ll n){
    ll res = 1;
    while(n>0){
        if(n&1){
            res *= a;
        }
        a*=a;
        n >>=1;
    }
    return res;
}

int n, total = 0;
string str;

int main(void){
    scanf("%d",&n);
    cin >> str;
    int cnt = 0;
    for(int i = 0;i < str.length(); i++){
        if(str[i] == 'x'){
            cnt++;
            continue;
        }
        if(cnt >= 3){
            // cout << cnt<<" ";
            total += cnt - 2;
        }
            cnt = 0;
    }
    // cout << cnt << "cnt\n";
    if(cnt > 0) total += cnt - 2;
    printf("%d\n", total);
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
	int n,dus=0,ob=0;
	cin >> n;
	char c;
	for(int i=0; i<n;i++){
		cin>>c;
		if(c=='x')dus++;
		else{
			if(dus>2)ob+=dus-2;
			dus=0;
		}
	}
	ob+=dus-2;
	cout<<ob;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
int n,c=0;
cin>>n;
string s;
for(int i=0;i<n-2;i++)
{
if(s[i]=='x'&&s[i+1]=='x'&&s[i+2]=='x')
c=c+1;}
cout<<c;
return 0;}

#include<cstdio>
using namespace std;
#define R register
int n;
char a[110];
inline void read(R int &x)
{
	x = 0;R char ch = getchar();R bool f = false;
	for(;ch < 48 || ch > 57;ch = getchar())f |= (ch == '-');
	for(;ch > 47 && ch < 58;ch = getchar())x = (x << 3) + (x << 1) + (ch ^ 48);
	(f) && (x = -x);
}
int main()
{
	read(n);
	scanf("%s",a);
	R int cnt = 0;
	for(R int i = n - 1;i >= 2; --i)
	{
		putchar(a[i]);printf("%d ",i);
		if(a[i] == 'x' && a[i] == a[i - 1] && a[i] == a[i - 2])
		{
			cnt++;
			continue;
		}
	}
	printf("%d",cnt);
}

# include <bits/stdc++.h>

using namespace std;

# define rep(i,n) for(int i=0;i<n;i++)

int main()
{
	int n;
	cin >> n;

	string s;
	cin >> s;

	int flag = 0;
	int count = 0;

	rep(i,s.size())
	{
		if(s[i] == 'x')
		{
		//	cout << "yeah";
			flag++;

		}
		else
		{
			if(flag >= 3)
			{
				count = count + (flag - 2);
			}
			flag = 0;
		}
		// cout << flag << endl;
		// cout << count << endl;
	}
	if(flag > 0)
		{count = count + (flag - 2);}
	cout << count << endl;
	return 0;
}

#include <bits/stdc++.h>

using namespace std;

const int MAXN = 110;

int main(){
  ios_base:: sync_with_stdio(false); cin.tie(0);
  char msg[MAXN];
  int n;
  cin >> n;

  for(int i = 0; i < n; i++)
    cin >> msg[i];

  vector <int> resp;
  char last;
  int num_x = 0;
  for(int i = 0; i < n; i++){
    if (msg[i] == 'x')
    {
      num_x++;
    }
    else if (num_x >= 3)
    {
      resp.push_back(num_x);
      num_x = 0;
    }
    else
    {
      num_x = 0;
    }
    last = msg[i];
  }

  if (num_x > 0 && last == 'x')
    resp.push_back(num_x);

  int tot = 0;
  for(int i = 0; i < (int) resp.size(); i++)
    tot += resp[i] - 2;

  cout << tot << endl;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	int cnt = 0;
	int tot = 0;
	for(int i = 0; i < n; i++)
	{
		if(s[i] == 'x'){
			cnt++;
		}else{
			if(cnt > 2){
				tot += (cnt - 2);
			}
			cnt = 0;
		}
	}
	if(cnt == n) cout << cnt - 2  << "\n";
	else cout << tot << endl;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;

int main(){

      int n,i,count=0;
      cin >> n;
      string s;
      for (i=0;i<n;i++){
         cin >> s[i];
      }
      for(i=0;i<n-3;i++){
        if(s[i]=='x' && s[i+1]=='x'&& s[i+2]=='x')
            count++;

      else
        count;
      }
      cout<<count;

 return 0;
}

#include<bits/stdc++.h>
using namespace std;
int gcd(long long x,long long y)
{
	if(!y) return x;
	return gcd(y,x%y);

}
int main()
{
    char s[101];
    int i,j,k,n,m,ans,wns;
    cin>>n;
    for(i=1;i<=n;++i)
    {
    	scanf("%c",&s[i]);
    	if(s[i]!='x')ans=0;
    	else ans++;
    	if(ans>=3)++wns;
	}
	cout<<wns;
}

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 1;
const int mod = 1e9 + 7;
int a[maxn];
vector<int>r;
int main(){
    int n, f;
    cin >> n;
    for(int i = 0; i < n; i ++) cin >> a[i];
    for(int i = 0; i < n; i ++){
        f = 1;
        for(int j = i + 1; j < n; j ++)
            if(a[i] == a[j]) f = 0;
        if(f>0) r.push_back(a[i]);
    }
    cout << r.size() << endl;
    for(auto x:r) cout << x << " ";
    return 0;
}

#include <iostream>
#include <string>

using namespace std ;

int main () {

	int n,len1,i=0;
	char a[101];
	bool bol ;
	cin >> n ;
	for ( int i=0 ; i<n ; i++ ) cin >> a[i] ;
	len1=n;
	do {
		bol = true ;
		for (int j=0 ; j<n-2 ; j++) {
			if (a[i]=='x' && a[i+1]=='x' && a[i+2]=='x') {
				if (i>=n-3) {
					n--;
					bol = true; ;
					break ;
				}
				else {
					for (int s=i+2 ; s<n-1 ; s++ ) {
						a[s]=a[s+1];
						--n ;
						bol = false ;
						break ;
					}
				}
			}
			break ;
		}

	} while (bol==false);
	cout << len1-n ;

	return 0;
}

#include<iostream>
#include<string.h>
using namespace std;

int main(){
	int n;
	cin >> n;
	string s;
	cin >> s;
	int i = 0;
	while(i<n){
		if(s[i]!='x'){
			break;
		}
	i++;
	}
		cout << max(0,i-2) << endl;

}

#include <bits/stdc++.h>
using namespace std;

int n;
char s[109];
int cnt[109];
int ans;

int main(){
    scanf("%d\n",&n);
    scanf("%s",s);
    int len=strlen(s);
    if(s[0]='x') cnt[0]=1;
    for(int i=1;i<n;i++){
        if(s[i]=='x') cnt[i]=cnt[i-1]+1;
    }
    for(int i=n-1;i>=0;i--){
        if(cnt[i]>=3){
            ans+=cnt[i]-2;
            i-=cnt[i];
        }
    }
    printf("%d",ans);
    return 0;
}

#include <iostream>
#include <string>
#include <cmath>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    int ans = 0;
    int l = 0;
    for (int i = 0; i < n; i++)
        if (s[i] == 'x')
            l++;
        else if (l > 0) {
            ans += (l - 2);
            l = 0;
        }
    if (l != 0)
        ans += (l - 2);
    cout << ans << endl;
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
main(){
    int n,count=0;
    cin>>n;
    string s;
    cin>>s;
    for(int i=2;i<n;i++){
        if(s[i-1]=='x'&&s[i-2]=='x')
        count ++;
    }
    cout<<count;
}

#include <iostream>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<string>
#include <algorithm>
using namespace std;

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char** argv) {
	int n,i,ans=0,max,sum=0;
	char a;
	cin>>n;
	for(i=1;i<=n;i++)
	{
		cin>>a;
		if(a=='x')
		{
			ans++;
		}
		else
		{
			if(ans>=3)sum=sum+ans-2;
			ans=0;
		}
	}
	cout<<sum;
	return 0;
}

#define ll long long
#define loop(x,n) for(ll x = 0; x < n; x++)
#define f(n) for(ll i = 0; i < n; i++)

#include <iostream>
#include <string>
#include <unordered_map>
#include <cmath>
#include <cstring>
#include <algorithm>

using namespace std;

int main()
{
    ll n; cin >> n;
    string s; cin >> s;
    ll sum = 0;

    for(int i = 0; i != n;){
        int new_i = s.find_first_not_of ('x', i+1);
        //cout << new_i << endl;
        if(new_i == string::npos){new_i = n; break;}
        if(new_i - i > 2){sum += new_i - i - 2;}
        i = new_i;
    }
    cout << sum << endl;

    return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
#define pob pop_back
#define pf push_front
#define pof pop_front
#define mod 1000000007
int main(){
	#ifndef ONLINE_JUDGE
	freopen("C:\\Users\\msmut\\Documents\\Programming\\Input.txt","r",stdin);
	freopen("C:\\Users\\msmut\\Documents\\Programming\\Output.txt","w",stdout);
	#endif
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	ll n;
	cin>>n;
	string s;
	ll c=0,ans=0;
	cin>>s;
	ll st=0;
	for(ll i=0;i<s.size();i++)
	{
		if(s[i]=='x' and st==1 and i==s.size()-1)
		{
			if(c>=3)
			{
				ans+=c-1;
			}
		}
		else if(s[i]=='x' and st==1)
		{
			c++;
		}
		else if(s[i]=='x' and st==0)
		{
			c++;
			st=1;
		}
		else if(s[i]!='x' and st==1)
		{
			if(c>=3)
			{
				ans+=(c-2);
				c=0;
				st=0;
			}
			else
			{
				c=0;
				st=0;
			}

		}

	}
	cout<<ans<<"\n";
}

#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
void solve(){
	int t,cnt=0,best=0,y=0;
	cin>>t;
	string s;
	cin>>s;
	char u='x';
	for(int i=0;i<t;i++){
		if(best>=3){
			y+=abs(3-best);
		}
		if(s[i]==u){
			cnt++;
			best=max(best,cnt);
		}else{
			cnt=0;
			continue;
		}
	}cout<<y;
}
int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	solve();
	return 0;
}

#include <bits/stdc++.h>
#define ll long long int
#define shrek() int main()
using namespace std;
shrek(){
	ll n;
	cin>>n;
	char strs[100];
	for(ll i=1;i<=n;i++){
		cin>>strs[i];
	}
	ll a=1;
	ll b=1;
	for(ll i=1;i<=n;i++){
		if(strs[i]==strs[i+1]&&strs[i+1]=='x'){
			a+=1;
			if(b<a){
				b=a;
			}
		}else{
			a=1;
		}
	}
	if(b>=3){
		cout<<b-2;
	}
	else{
		cout<<0;
	}
	return 0;
}

#include <iostream>
using namespace std;

int main()
{
	int n, l = 0, mx = 0;
	string s;
	cin >> n >> s;
	for(int i = 0; i < n; i++)
	{
		if(s[i] == 'x') l++, mx = max(mx, l);
		else mx = max(mx, l), l = 0;
	}
	if(mx > 2) cout << mx - 2;
	else cout << 0;
}

#include<bits/stdc++.h>
#include<iostream>
using namespace std;

int main(void)
{
    int n,cnt=0;
    cin>>n;
    string s;
    while(n--)
    {
        cin>>s;
        for(int i=0;i<n;i++)
        {
            if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x')
            {
                cnt++;
            }
        }
    }
    cout<<cnt<<endl;
}

#include <iostream>
#include <string>
#include <bits/stdc++.h>

using namespace std;

#define pf printf
#define sf scanf
#define elf else if
#define Size 101

int main()
{
//    ios_base::sync_with_stdio(false);
//    cin.tie(NULL);
//    cout.tie(NULL);

    char s[Size];
    int in,len = 0,numX = 0,needToRemove = 0;
    bool tr = false;

    sf("%d",&in);
    sf("%s",s);

    for(int i = 0; i < in; i++)
    {
        if(s[i] == 'x')
        {
            numX += 1;

            if(numX == 3)
            {
                needToRemove += 1;
                numX = 0;
            }
        }

        else{
            numX = 0;
        }
    }

    printf("%d\n",needToRemove);

    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int cha[n];
    for(int i=0;i<n;i++)
    {
        cin>>cha[i];
    }
    int ct=0;
    vector<int > rs;
    int ans=0;
    for(int i=0;i<n;i++)
    {
        if(cha[i]=='x')
        {
            ct++;
        }
        else
        {
            if(ct>=3)
            {
                ans=ans+(ct-2);
            }
            ct=0;
        }
    }

    cout<<ans;

    return 0;
}

#include<iostream>
#include<vector>
using namespace std;
int main()
{
    int n; cin >> n;
    string s; cin >> s;
    vector<char> vec(n);
    for(int i=0;i<n;i++){
        vec[i]=s[i];
    }
    int counter=0;
    for(int i=0;i<vec.size();i++){
        if(vec[i]=='x' && vec[i+1]=='x' && vec[i+2]=='x'){
            counter++;
            vec.erase(vec.begin()+i);
            i=i-1;
            if(vec.size()<3) break;
        }
    }
    cout << counter << endl;
}

//Bismillahir Rahmanir Rahim
#include <bits/stdc++.h>
using namespace std;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n,c=0;
    cin>>n;
    string s;
    cin>>s;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='x')
        {
            c++;

        }
        else
            c=0;
    }
    if(c>=3)
    cout<<c-2<<endl;
    else
        cout<<0;
}

#include <iostream>
#include <string>
using namespace std;
int main(){
    bool start=false;
    int i,j,n,a=0,b=0;
    string s;
    cin >>n >> s;
    for(i=0;i<n;i++){
        if(s[i]=='x'&&i<n-2){
            j=i;
            while(j!=n){
                if(s[j]=='x'){
                    a++;
                }
                else{
                    break;
                }
                j++;
            }
            if(a>=3){
                b+=a-2;
            }
            i = j;
        }
    }
    cout << b;
}

#include<bits/stdc++.h>
using namespace std;
char s[1000];
int i,j,k,ans,n,m;
int main()
{
	cin>>n;
	for(i=1;i<=n;++i)
	{
		cin>>s[i];
		if(s[i]=='x')++ans;
		if(ans>=3)ans=0,++m;
		if(s[i]!='x')ans=0;
	}
	cout<<m;
}

#include<bits/stdc++.h>
using namespace std;

int main(){
    int n , count =0 , ex=0 ;
    cin >> n;
    string s ; cin >> s ;
    for( int i=0 ; ; )
    {
        if( s[i]=='x' and s[i+1]=='x' and s[i+2]=='x'){
            count += 3 ;
            ex += 3 ;
            //cout << i << endl;
            i++ ;
            //cout << i << endl;
            i++ ;
            //cout << i << endl;
            i++ ;

            if( i >=n ) break;
        }
        else{
            if( s[i]=='x' ) ex++ ;
            //cout << i << endl;
            i++ ;
            if( i>= n ) break;
        }
    }
    //cout << ex << " " << count << endl;
    //cout << ex-(count)+1 << endl;

    if( count ==0 ) cout << 0 << endl ;

    else if( count == 3 ) cout << 1 << endl;

    else if( count >3 and ex%3==0 ) cout << count-2 << endl;

    else if( count >3 and ex%3 >0 )
    {
        if( ((count/3) -1) + (ex%3) >= 3 )
            cout << count-2 + 1 << endl;
    }

    /*

    */
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int chr[n];
    for(int i=0;i<n;i++)
    {
        cin>>chr[i];
    }
    int ct=0;
    vector<int > rs;
    for(int i=0;i<n;i++)
    {
        if(chr[i]=='x')
        {
            ct++;
        }
        else
        {
            if(ct>=3)
            {
                rs.push_back(ct);
            }
            ct=0;
        }
    }

    int ans=0;
    for(int i=0;i<rs.size();i++)
    {
        ans=ans+(rs[i]-1);
    }
    cout<<ans;

    return 0;
}

#include <iostream>
#include <string>
#include <bits/stdc++.h>

using namespace std;

#define pf printf
#define sf scanf
#define elf else if
#define Size 101

int main()
{
//    ios_base::sync_with_stdio(false);
//    cin.tie(NULL);
//    cout.tie(NULL);

    char s[Size];
    int in = 0,len = 0,numX = 0,needToRemove = 0;
    bool tr = false;

    sf("%d",&in);
    sf("%s",s);

    for(int i = 0; i < in; i++)
    {
        if(s[i] == 'x')
        {
            numX += 1;

            if(numX > 3 && tr == false)
            {
                continue;
            }
        }

        else{
            tr = true;

            if(numX == 3 && tr == true)
            {
                needToRemove += 1;
                tr = false;
                numX = 0;
            }

            else{continue;}
        }
    }

    if(numX > 3)
    {
        needToRemove = numX - 2;
    }

    printf("%d\n",needToRemove);

    return 0;
}

#include <iostream>
#include<string>
#include <iomanip>
#include <stdio.h>
#include <algorithm>
#include<cmath>
#include<set>
#include<vector>
#include<math.h>
#include <string.h>
using namespace std;
int main()
{
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    int n;
    cin >> n;
    string a;
    cin >> a;
    long long s = 0;
    int d = 1;
    for (int i = 0; i < n; i++)
    {

        if (a[i] == 'x')
        {
            for (int j = i + 1; j < n; j++)
            {

                if ((a[j] != 'x') && (j>(i+2)))
                {
                    s += j - i - 2; i = j; d--; break;
                }
                if (a[j] != 'x')
                {
                    d--; i = j; break;
                }
            }
            if (d > 0) { s = n - i - 1-1; break; }
        }

    }
    cout << s << endl;
}

#include<bits/stdc++.h>
#include <string>
using namespace std;
int main()
{
    int n , x , ans;
    string s ;
    cin>>n>>s;
    for(int i=0;i<=s.length();i++)
    {
        if(s[i]=='x')
            x++;
        else
            x=0;
        if(x>=3)
            ans++;

    }
    cout<<ans;
}

#include<bits/stdc++.h>
#define ll long long int
#define YES cout<<"YES"<<endl
#define NO cout<<"NO"<<endl
#define yes cout<<"yes"<<endl
#define no cout<<"no"<<endl

using namespace std;

int main()
{
   int n,l,cnt=0,c=0;
   string s;
   cin>>n>>s;
   l=s.size();
   for(int i=0; i<l; i++)
   {
       if(s[i]=='x') cnt++;
   }
   if(cnt==l)
   {
       cout<<l-2<<endl;
   }
   else
   {
       for(int i=0; i<l-2; i=i+3)
       {
           if(s[i]=='x' && s[i+1]=='x' && s[i+2]=='x')
           {
               c++;
           }
       }
       cout<<c<<endl;
   }
}

#include<iostream>
#include<cstring>
#include<cstdio>
#include<string.h>
#include<cmath>
using namespace std;
int  main()
{
    char str[105];
    int n;
    while(scanf("%d",&n)!=EOF)
    {
        int ans=1;
        int count=3;
        int flag=1;
        int i,j;
        scanf("%s",str);
        if(str[0]!='x'||str[1]!='x'||str[2]!='x')
        {
            printf("0\n");
            continue;
        }
        for(i=3;i<=n;i++)
        {
            if(str[i]=='x'&&flag)
            ans++;
            if(str[i]!='x')
            {
                count=0;
                flag=0;
            }
            if(str[i]=='x'&&!flag)
            {
                count++;
                if(count>=3)
                {
                    flag=1;
                    ans++;
                }
            }
        }
    printf("%d\n",ans);
    }
    return 0;
}

#include<cstdio>
#include<iostream>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<utility>
#include<functional>
using namespace std;

int main()
{
	ios::sync_with_stdio(false);
	int n, res = 0;
	string s;
	cin >> n;
	cin >> s;
	int len = s.size(), ok = 0, cur ;
	for (int i = 2; i < len; i++)
	{
		if (s[i] == 'x' && s[i - 1] == 'x' && s[i - 2] == 'x' && !ok)
		{
			ok = 1;
			cur = 1;
			continue;
		}
		if (s[i] == 'x' && ok && i!=len-1)
			cur++;
		else if (s[i] == 'x'&&ok&&i == len - 1)
		{
			cur++;
			res += cur;
		}
		else if (s[i] != 'x'&& ok)
		{
			res += cur;
			ok = 0;
		}
	}
	cout << res << endl;
	return 0;
}

#include <iostream>
#include <map>
#include <string>
#include <vector>
#include <cstdlib>
#include <algorithm>

using namespace std;

int main()
{
    int n,cont = 0,total = 0;cin>>n;
    string a;cin>>a;
    for(int i = 0;i < n-1;i++)
    {
        if(a[i] == 'x' && a [i+1]=='x')
        {
            cont++;
            if(i == n-2 && cont > 2)
                total = cont-1;
        }
        else if(a[i] == 'x')
        {
            cont = 0;
            if(cont > 1)
                total+=(cont-1);
        }

    }
    cout<<total;
}

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <string>
#include <algorithm>
#include <time.h>
//#include <math.h>
#include <cmath>
#include <fstream>
#include <deque>
#include <unordered_map>
#include <unordered_set>
#include <stdlib.h>
#include <iomanip>
#include <cstdio>
//#include <stdio.h>

using namespace std;

#define flu fflush(stdout)
#define gg return 0
#define mp make_pair

long long mod = /*27449*/998244353;
int inf = 1e9;
double eps = 1e-2;

ifstream in("input.txt");
ofstream out("output1.txt");

int main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	int ans = 0;
	int c = 0;
	for (int i = 0; i < s.size(); i++)
	{
		if (s[i] == 'x')
		{
			c++;
		}
		else
		{
			if (c != 0)
			{
				ans = max(0, c - 2);
				c = 0;
			}
		}
	}
	cout << ans;
	gg;
}

#include<bits/stdc++.h>
using namespace std;

int main(){
    int n;
    cin>>n;
    string s;

   for(int i=0;i<n;i++){
      cin>>s[i];
   }

    int c=0;

    if(n<=2){
        cout<<0;
    }
    else{
    for(int i=0;i<n-3;i++){
        if(s[i]=='x'){
            if(s[i+1]=='x' && s[i+2]=='x')
                  c++;
        }
    }

    cout<<c;
    }
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
	string a;
	cin >> a;
	vector<int>v;
	int i,cnt=0;
	for(i=0;i<a.size();i++)
	{
		if(a[i]!='x')
		v.push_back(i+1);
	}
	if(v.size()==0)
	{
		int k=count(a.begin(),a.end(),'x');
		cout<<k-2;
	}
	if(v.size()==1)
	{
		if(v[0]-3>0)
		cnt+=v[0]-3;
		if(a.size()-v[0]-2>0)
		cnt+=a.size()-v[0]-2;
		cout<<cnt;
	}
	else
	{
		if(v[0]-3>0)
		cnt+=v[0]-3;
		if(v[v.size()-1]!=a.size())
		{
			if(a.size()-v[v.size()-1]-2>0)
			cnt+=a.size()-v[v.size()-1]-2;
		}
		for(i=1;i<v.size();i++)
		{
			if(v[i]-v[i-1]-3>0)
			cnt+=v[i]-v[i-1]-3;
		}
		cout<<cnt;
	}
	return 0;
}

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define fast ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int main()
{
    int n;string a;
    cin>>n>>a;
    int l,lar,i;
    l=0;
    lar=0;
    for(i=0;i<n;i++)
    {
        if(a[i]=='x')
            l++;
        else
        {
            if(l>lar)
                lar=l;
            l=0;
        }
    }
    if(lar<3)
        cout<<"0";
    else
        cout<<lar-2;
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

#define sz(s) (int)(s.size())
#define ll long long
#define all(s) s.begin(), s.end()
#define rep(a, b, c) for(int a = b; a <= c; ++a)
#define per(a, b, c) for(int a = b; a >= c; --a)
#define _ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define open(x) freopen(x".in","r",stdin); freopen(x".out","w",stdout);
const int A=1005;

ll n,ans=-2,mx,cnt;
string s;

int main(){ _
	//open("")
	cin>>n;
	cin>>s;
	rep(i,0,n-1){
		if(s[i]=='x'){
			ans++;
		}
		else{
			ans=-2;
		}
		cnt+=mx;
		mx=max(mx,ans);
	}
	cout<<mx;

}

#include<stdio.h>

int main()
{
	char str;
	int n;
	while(scanf("%d",&n)!=EOF)
	{
		int sign =0,num = 0;
		for(int i=1;i<=n;i++)
		{
			scanf("%c",&str);
		if(str=='x')
			{
				sign++;
				if(i==n && str == 'x')
				{
					sign++;
				num+=sign-2;
			}
			}
			else {
				if(sign>2)
			{	num+=(sign-2);}
				sign =0;
			}
        }
        printf("%d\n",num);
	}
	return 0;
}

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;
int count_X(string s){
	int m = s.size();
	int k = 0;
	int kl = 0;
	for(int i=0;i<m;i++){
		if(s[i]=='x'&&i<m-1)   ++k;
		else{
			if(i==m-1&&s[i]=='x')   ++k;
			if(k>kl)   kl = k;
			k = 0;
		}
	}
	return kl;
}
bool Filename(string s){
	int m = s.size();
	for(int i=0;i<m-2;i++){
		if(s[i]=='x'&&s[i+1]=='x'&&s[i+2]=='x')   return true;
	}
     return false;
}
int main()
{
	int n;
	cin>>n;
	string s;
	s.resize(n);
	cin>>s;
	if(Filename(s))    cout<<count_X(s)-2<<endl;
	else cout<<"0"<<endl;
	return 0;

}

#include <bits/stdc++.h>

using namespace std;

int main(){
    int n, i, co = 0;
    scanf("%d ", &n);

    char str[n];
    scanf("%s", str);

    if(str[0] != 'x' || str[1] != 'x' || str[2] != 'x'){
        printf("0\n");
        return 0;
    }

    for(i = 0; i < n - 2; i++){
        if(str[i] == 'x' && str[i + 1] == 'x' && str[i + 2] == 'x'){
            co++;
        }
    }

    printf("%d\n", co);

    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a,p=0,q=0;
    cin>>a;
    char s;
    for(int i=0;i<a;i++)
    {
        cin>>s;
        if(s=='x')
        {
            p++;
        }
        else
        {
            if(p<=2)
            p=0;
        }
    }
   if(p==a)
   {
       cout<<a-2<<endl;
       return 0;
   }
    if(p>2&&p<a)
    {
        for(int i=1;i<=p;i++)
        {
            p=p-i;
            if(p==2)
            {
                cout<<i<<endl;
            }
        }
    }
    else
    {
        cout<<"0"<<endl;
    }

    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
    string s;
    cin>>s;
    int a=0,b,c,d;
    while(s.find("xxx")!=-1){
        b=s.find("xxx");
        s.erase(b,1);
        a++;
    }
    cout<<a;
}

#include<iostream>
#include<cmath>
#include<string>
#include<vector>
#include<algorithm>
using namespace std;

int main() {

int n;
cin>>n;
string s;
cin>>s;
int k=0,r=0;
for (int i=0;i<n;i++){
     if (s[i]=='x'){
          k++;
     }else{
          if (k>2){
               r=k-2;
          }
          k=0;
     }

}
if (k>2){
     r+=k-2;
}

cout<<r;

}

#include <iostream>
#include <string>
#include<algorithm>
#include <cstdio>
#include <vector>
#include<numeric>
using namespace std;

void main()
{

	int n,b=0,k=0;
	string s;
	cin >> n >> s;
	int t = count(s.begin(), s.end(), 'x');
	if (t > 2)
		for (size_t i = 1; i < n - 1; i++)
		{
			if (s[i] == 'x' && s[i - 1] == 'x' && s[i + 1] == 'x' && k == 0) { k = 1; i += 2; b += 1; }
	        else k = 0;
			while (k==1 && i<n-1)
			{
				if (s[i] == 'x')
				{
					i += 1;
					++b;
				}
				else k = 0;

			}
	}

	cout << b;

}

#include<bits/stdc++.h>
using namespace std;
main()
{
	int n;
	cin >> n;
	string s;
	cin >> s;
	int count  = 0,ans = 0,flag = 0;
	s = s + '1';
	for(int i=0; i<n; i++)
	{
		if(s[i] == 'x')
		{
			if(s[i+1] == 'x')
				count++;
			if(s[i+1] != 'x' && count >2)
			{
				count++;
				ans = count - 2;
				count = 0;
				flag = 1;

			}
		}

	}
	if(flag = 1)
		cout << ans;
	else
		cout << count;
}

#include<bits/stdc++.h>
using namespace std;
int main() {
	int n,b=0,c=1;
	string a;
	cin>>n;
	for(int i=0; i<n; i++)
		while(cin>>a[i]){
		 if(a[i]=='x') {
			 b+=1;
	break;}
else {
	if(b>=3) c=b-2;
	b=0;
	break;
}}
if(b==n-1) cout<<b-2;
else
cout<<b-2*c;
return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int a,i,j=0,k=0;
    string b;
    cin>>a>>b;
    for(i=0;i<a;i++)
    {
        if(b[i]=='x'){j++;}
        else if(b[i]!='x'){if(j>2){k++;j=0;}else{j=0;}}
    }
    if(k){cout<<k;}
    else{cout<<j-2;}
}

#include <iostream>
#include <string>
using namespace std;
int main()
{
	int n,c;
	cin>>n;
	string h;
	cin>>h;
	for (int i=0; i<n; i++)
	{
		if(h[i]=='x')
			c++;
		if (h[i+1]=='x')
			c++;
		if (h[i+2]=='x')
			c++;
	}
	if(c!=0)
		cout<<c;
	if (c==0)
		cout<<"0";
}

#include <iostream>
#include <vector>
#include <cstdio>
#include <string>

#define pb push_back
#define mp make_pair
#define fr first
#define sc second
#define MOD 1000000007
#define len(x) x.size()
#define min3(a, b, c) min(a, min(b, c))
#define max3(a, b, c) max(a, max(b, c))
#define all(v) v.begin(), v.end()
#define alla(a,n) a, a + n

using namespace std;

using std::cout;
using std::cin;
using std::vector;
using std::pair;
using std::string;
using std::ios_base;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pll> vpll;
typedef vector<vll> vvll;
typedef vector<string> vs;

int32_t main()
{
	#ifndef ONLINE_JUDGE
		freopen("input.txt", "r", stdin);
		freopen("output.txt", "w", stdout);
	#endif

	ios_base::sync_with_stdio(false);
	cin.tie(NULL); cout.tie(NULL);

	int N;
	cin >> N;

	string message;
	cin >> message;

	int num_removals = 0;

	int num_x = 0;
	bool other_found = false;
	for (int i = 0; i < N; i++)
	{
		if (message[i] != 'x' && num_x >= 3)
		{
			other_found = true;
			num_removals += num_x - 2;
			num_x = 0;
		}
		else
			num_x++;
	}

	if (!other_found)
		num_removals += num_x - 2;
	cout << num_removals << "\n";
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,count=0,countt=0,j=0,k=0;
    cin>>n;
    string s;
    cin>>s;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='x'){
            count++;
            k=k+count;}
        else
        {
            countt++;
            count=0;
        }
    }
    while(k>2)
    {
        j++;
        k--;
    }
    cout<<j<<endl;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    string s;
    cin>>n>>s;
    int k=0;
    int maxx=0;
    int ans=0;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='x')
        {
        k++;
            maxx=max(maxx,k);
        }
        else
        {
            ans+=k-2;
            k=0;
        }
    }
    cout<<k;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
int n;
cin>>n;
string s;
cin>>s;
int k;
int ans=0;
for(int i=0;i<n;i++)
{
if(s[i]=='x')
{
k=i;
while(s[i]==s[k])
{
k++;
}
if(k-i>=3)
{
ans+=k-2;
}
i=k-1;
}
}
cout<<ans<<endl;
}

#include <iostream>
#include <string>
#include <cstdio>
#include <algorithm>
#include <set>
#include <vector>
#include <map>

using namespace std;

int main()
{
#ifdef MY_DEBUG
  freopen("input.txt", "r", stdin);
  freopen("output.txt", "w", stdout);
#endif

  int n, k;
  cin >> n >> k;
  vector<vector<int> > v(4);
  for(int i = 0; i < v.size(); i++)
  {
    v[i].resize(n, 0);
  }

  if(k == 2 * (n - 2))
  {
    for(int i = 1; i < 3; i++)
    {
      for(int j = 1; j < n-1; j++)
      {
        v[i][j] = '#';
      }
    }
  }
  else
  {
    bool fl = false;
    for(int i = 1; i < 3; i++)
    {
      if(fl)
        break;
      for(int j = 1; j < n / 2; j++)
      {
        if(k > 1)
        {
          v[i][j] = v[i][n - j - 1] = 1;
          k-=2;
        }
        else
        {
          fl = true;
          break;
        }
      }
    }
  }

  if (k == 1)
  {
    v[2][n / 2] = 1;
    k--;
  }

  cout << "YES" << endl;
  for(int i = 0; i < 4; i++)
  {
    for(int j = 0; j < n; j++)
    {
      if(v[i][j] == 0)
        cout << '.';
      else
        cout << '#';
    }
    cout << endl;
  }

  return 0;
}

#include<bits/stdc++.h>
#include <string>
using namespace std;
int main()
{
    int n , x , ans;
    string s ;
    cin>>n>>s;
    for(int i=0;i<=s.length();i++)
    {
        if(s[i]=='x')
            x++;
        else
            x=0;
        if(x>3)
            ans++;

    }
    cout<<ans;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    string s;
    cin>>n>>s;
    int k=0;
    int maxx=0;
    int ans=0;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='x')
        {
        k++;
            maxx=max(maxx,k);
        }
        else
        {   if(k>=3)
            ans+=k-2;
            k=0;
        }
    }
    cout<<ans;
}

#include<bits/stdc++.h>
using namespace std;
char s;
int main()
{
    int n,k=0,min1=0,p=1;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>s;
        if(s=='x'){
            k++;
            p=0;
        }else{
            if(p==0){
            min1+=k-2;
            if(n==100){
            cout<<'+'<<k;}

            k=0;
            p=1;}
        }
    }
    if(p==0){
    min1+=k-2;}
    if(min1<0)cout<<0;else
    cout<<min1;
}

#include <bits/stdc++.h>
#include <numeric>
using namespace std;
int main() {
    int n ,count=0;
    cin >> n;
    string x;
    cin >> x;
    for(int i=0;i<n;++i)
    {
        if(x[i]=='x')
        {
            count++;
        }
    }
    if(count>2)
    cout<<(count-2);
    else
        cout<<0;
    }

#include <bits/stdc++.h>
#define ll long long
#define f first
#define s second
#define jig_saw ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;
int main()
{
jig_saw
ll n , cnt=0,ans=-1,sum=0,k;
cin >> n;
string s;
ll a[n+5],b[n+4] ,count=0;
 cin >> s;
 for (int i=0;i<n;i++)
 {
     if (s[i]=='x')
     {
         count++;
     }
     else {ans = max(ans,count-3+1); count = 0;     }
 }
 if (ans==-1){ ans = max(ans ,count-3+1);}
 if (ans<0){ans=0;}
 cout << ans;
return 0;
}

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<iostream>
#include<map>

using namespace std;
map<int,int> m;
int main()
{
    int n;
    cin>>n;
    getchar();
    char str[111];
    cin>>str;
    int cnt=0,ans=0,flag=0;
    for(int i=0;i<n;i++)
    {
        if(str[i]=='x')
        {
            cnt++;
            flag=1;
        }
        else if(cnt!=0&&str[i]!='x')
        {
            ans+=cnt-2;
            cnt=0;
        }
        if(str[i]=='x'&&i==n-1&&cnt>=3)
        {
            ans+=cnt-2;
        }
    }
    if(!flag)
        cout<<"0"<<endl;
    else
        cout<<ans<<endl;
    return 0;
}

#include <iostream>
#include<string>
#include <iomanip>
#include <stdio.h>
#include <algorithm>
#include<cmath>
#include<set>
#include<vector>
#include<math.h>
#include <string.h>
using namespace std;
int main()
{
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    int n;
    cin >> n;
    string a;
    cin >> a;
    long long s = 0;
    int d = 1;
    for (int i = 0; i < n; i++)
    {

        if (a[i] = 'x')
        {
            for (int j = i + 1; j < n; j++)
            {
                if (a[j] != 'x')
                    d--;
                if ((a[j] != 'x') && (j - i > 2))
                {
                    s += j - i - 2; i = j; d--; break;
                }
            }

        }
        if (d) { s = n - 1 -1; break; }
    }
    cout << s << endl;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int q;
    int c=0;
    int b=0;
    vector <int> a;
    cin>>q;
    string s;
    cin>>s;

    for(int i=0; i<q; i++){
        if(s[i]=='x'){
            a.push_back(s[i]);
        }
        else{
            a.push_back(' ');
        }
    }
    for(int i=0; i<q; i++){
        if(a[i]=='x'){
           c+=1;
           if(c==q){
                cout<<q-2;
           }
        }
        else{
            if(c!=0){
                if(c>=3){
                   c=c-(c-1);
                   cout<<c;
                }
                else{
                    cout<<0;
                }
            }
            c=0;
        }
    }
    for(int i=0; i<q; i++){
        if(a[i]==' '){
            b+=1;
            if(b==q){
                cout<<0;
            }
        }
    }
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main () {
	int n,cnt=0,g=-1,d,k=0;
	cin>>n;
	char b;
	string s="";
	for (int i=0; i<n; i++)
	   {
	   	   cin>>b;
	   	   s=s+b;
	   }

	while (n>0)
	{
	for (int i=g+1; i<s.size(); i++)
	    {
	    	if (s[i]=='x')
	    		g=i;
	    	else
	    	break;
		}
	  	d=g-cnt;
	  	cnt=g;
	  	if (d>=2)
	  	  k=k+d-1;
	  	if (cnt==s[s.size()-1])
	  	   break;

    n--;
    }
    cout<<k;

	return 0;
}

#include<bits/stdc++.h>
using namespace std;
main()
{
   string str;
   int n,c=0;
   cin>>n>>str;
   for(int i=0;str[i]!='\0';i++)
   {
       if(str[i]=='x'&&str[i+1]=='x'&&str[i+2]=='x')
       {
           str[i]='3';
           c++;
       }
   }
   cout<<c<<endl;
   for(int i=0;str[i]!='\0';i++)
   {
       if(str[i]!='3')cout<<str[i];
   }
}

#include <bits/stdc++.h>
using namespace std;

int main() {
    string s;
    int ans = 0;

    cin >> s;
    int cnt = 0;
    for(auto& i: s) {
        if(i != 'x') {
            if(cnt > 2) ans += cnt - 2;
            cnt = 0;
        } else cnt ++;
    }

    cout << ans << endl;
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
	char a[101];
	int b[20]={0};
	int n,c=0,flag=0;
	cin>>n;
	for(int i=0;i<n;i++)
	{
		cin>>a[i];
	}
	cout<<endl;
	/*for(int i=0;i<n;i++)
	{
		cout<<a[i];
	}*/
	int j=0;
	for(int i=0;i<n;i++)
	{
		if(a[i]=='x')
		{
			c++;
		}
		else
		{
			flag = 1;
			b[j]=c;
			j++;
			c=0;
		}
		if(flag == 0)
		{
			b[j]=c;
		}
	}
	/*for(int i=0;i<n;i++)
		cout<<b[i];*/
	int sum=0,d;
	for(int i=0;i<n;i++)
	{
		if(b[i]>=3)
		{
			d = b[i]-2;
			sum = sum + d;
		}
	}
	if(sum==0)
		cout<<'0';
	else
		cout<<sum;

	return 0;
}

#include<bits/stdc++.h>
#include <sstream>
using namespace std;
int main()
{
   int k=0,t=0,flag=0,n;
   cin>>n;
   string a;
   cin>>a;
   for(int i=0;i<a.size();i++)
   {
       if(a[i]=='x')
       {
           k++;
       }
       else
       {
           if(k>=3)
           {
                t=k-2;
                flag=1;
           }
           k=0;
       }
   }
   if(flag==0)
   {
       t=k-2;
   }
   cout<<t;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,count=0,countt=0,j=0,k;
    cin>>n;
    string s;
    cin>>s;
    for(int i=0;i<n;i++)
    {
        if(s[i]=='x'){
            count++;
            k=count;}
        else
        {
            countt++;
            count=0;
        }
    }
    while(k>2)
    {
        j++;
        k--;
    }
    cout<<j<<endl;
}

#include<cstdio>
#include<algorithm>
#include<cctype>
#include<cstring>
#include<iostream>
#include<cmath>
#define LL long long
#define INF (2139062143)
#define N (100005)
using namespace std;
int n,tot,ans;
char c[N];
template <typename T> void read(T&t) {
	t=0;
	bool fl=true;
	char p=getchar();
	while (!isdigit(p)) {
		if (p=='-') fl=false;
		p=getchar();
	}
	do {
		(t*=10)+=p-48;p=getchar();
	}while (isdigit(p));
	if (!fl) t=-t;
}
int main(){
	read(n);
	scanf("%s",c+1);
	for (int i=1;i<=n;i++){
		if (i==1||c[i]!='x'){
			if (tot>2) ans+=tot-2;
			tot=0;
		}
		else tot++;
	}
	if (tot>2) ans+=tot-2;
	printf("%d",ans);
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
string x,y;
int i,n,a,b,k;
int main (){
cin>>a>>y;
for (i=a; i>=0; i--){
    if (y[i]==120) k++;
    else { k=0;continue;}
    if (k==3) {y.erase(i,1); b++; k=0;}

}
cout<<b;
}

#include <bits/stdc++.h>
#define maxn 120
#define inf 0x3f3f3f3f
using namespace std;
int n,ct;
char s[maxn];
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>s[i];
		if(s[i]=='x')	ct++;
	}
	if(n<=2){
		cout<<0<<endl;
		return 0;
	}
	if(ct==n){
		cout<<n-2<<endl;
		return 0;
	}
	int cnt=0;
	for(int i=3;i<=n;i++){
		if(s[i]=='x'&&s[i-1]=='x'&&s[i-2]=='x'){
			cnt++;
			s[i]='o';
		}
	}
	cout<<cnt<<endl;
	return 0;
}

#include <iostream>
#include <string>
// #include <cstdlib>
// #include <cmath>
#include <array>
// #include <vector>
// #include <algorithm>
// #include <set>
// #include <map>

using namespace std;

int main(){
	int n;
	cin >> n;

	string error;
	cin >> error;

	int remove_x = 0;
	int xcnt = 0;

	for(int i = 0; i < n; i++){
		if(error[i] == 'x'){
			xcnt++;
		}
		else{
			// cout << "x=" << xcnt << endl;
			if(xcnt >= 3){
				remove_x += (xcnt - 2);
			}
			xcnt = 0;
		}

	}
	cout << remove_x << endl;
}

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int n,count=0;
    cin>>n;
    string s;
    cin>>s;
    for(int i=0;i<s.size();i++)
    {
        if(s.at(i)=='x')
        {
            count++;
        }
    }
    if(count<3)
    {
        cout<<"0"<<endl;
    }
    else
        cout<<count-2<<endl;

       return 0;
}