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

int main()

{
    long long int a,b,n,k,m=240,sum=0,p;
    cin >> n >> k;
    if(n>=1 && n<=10 && k>=1 && k<=240)
    {
        if(k>=236 && k<=240)
        {
            printf("0\n");
        }
        else if(k!=m)
        {
    a=m-k;
    for(b=1;b<=n;b++)
    {
        sum=5*b+sum;
        if(sum<=a)
        {
            p=sum+5*(b+1);
            if(p>a)
            {
                break;
            }
        }

    }
    if(b>n) printf("%lld\n",n);
    else printf("%lld\n",b);
    }
    }
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int n,k,sum=0,ans;
    cin>>n>>k;
    int t=240-k;
    for(int i=1;i<=n;i++)
    {
        sum=sum+5*i;
        if(sum<=t)
        {

        }
        else
        {
           ans=i-1;
        break;
        }
        ans=i;
    }
    cout<<ans<<endl;
    return 0;
}//ffsdskoddks//

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,k,i=1,j=0;
    cin>>n>>k;
    int sum=0;
    k=240-k;
    while(sum<=k)
    {
        if(sum==k)
        {
            if(j<=n)
    cout<<j;
    else
    cout<<n;
            return 0;
        }
        else
        {
        sum=sum+5*i;
        i++;
        j++;
        }
    }

    if(j<=n)
    cout<<j-1;
    else
    cout<<n;

}

#include <iostream>
using namespace std;
int main()
{
    int n  ,k;
    scanf("%d%d",&n,&k);
    int m = (60*4) - k;
    int lo=0 , hi=n;
    while (lo < hi)
    {
        int mid = lo + (hi-lo+1)/2;
        int s=0;
        for (int i=0 ; i<=mid;i++)
        {
            s += 5*i;
        }
        if (s<= m) lo=mid;
        else hi=mid-1;
    }
    cout<<lo;
    return 0;
}

#include <cstdio>
#include <algorithm>
#include <cstring>
#include <queue>
#include <vector>
#define MaxN 1005
using namespace std;

int t=240,N,T;
int main()
{
	scanf("%d%d",&N,&T);
	t-=T;
	int pos=0;
	while(pos<N&&(pos+1)*(pos+2)*5/2<=t)
		pos++;
	printf("%d",pos);
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int i,n,m;
	cin>>n>>m;
	m=240-m;
	for(i=0; (i+1)<=n && (i+1)*(i+2)*5/2<=m; i++);
	cout<<i;

}

#include<bits/stdc++.h>

using namespace std;
int main()
{
	int n,k,c=0,x=0,p;
	cin>>n>>k;
	p=240-k;
	while(x<=p)
	{
		c++;
		x+=5*c;
	}
	cout<<min(n,--c);
	return 0;
}

#include <iostream>

using namespace std;
#include  <string>
int main()
{
    int j,h,i,n,k;
    i=0;
    j=1;
    h=5*j+i;
    cin>> n >> k;
    while (h<=4*60-k && j<= n){
        i+=5*j;
        j++;
        h=5*j+i;
    }
    cout<< j-1;
    return 0;
}

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

int main() {
	long long int n,k,m,c;
	cin>>n;
	cin>>m;
	c=240-m;
	k=c%5;
	c=c-k;

	vector<long long int>a;
	for(long long int i=0;i<=n;i++)
	{
	    a.push_back(i*5);

	}
	for(long long int i=1;i<=n;i++)
	{
	    a[i]=a[i]+a[i-1];
	}
	vector<long long int>::iterator upper;
	upper=upper_bound(a.begin(),a.end(),c);
cout<<upper-a.begin()-1;

	return 0;
}

#include <iostream>

using namespace std;
int n,k,mid,r,l,s,i,maxi,maximid;
int main()
{
    cin>>n>>k;
    if (k>235)
    {
        cout<<mid;
        return 0;
    }
    else
    {
        r=n;
        l=1;
        while(l!=r)
        {
            s=0;
            mid=(l+r+1)/2;
            for (i=1;i<=mid;i++)
                s=s+5*i;
            if(s==240-k)
            {
                cout<<mid;
                return 0;
            }
            else if(s<240-k)
            {
                l=mid;
                /*if (240-s>maxi)
                {
                    maxi=240-s;
                    maximid=mid;
                }*/
            }
            else r=mid-1;
        }

        cout<<l;
        return 0;
    }

}

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

typedef long long int ll;
#define loop(i,s,e) for(ll i=s;i<e;i++)
#define test ll x;cin>>x;while(x--)
#define pb push_back
#define vec vector<ll>
#define sortvec(x) sort(x.begin(),x.end())
#define sz(x) x.size()

int main () {
	ios_base::sync_with_stdio(false);
    cin.tie(NULL);
	ll n,k;
	cin>>n>>k;
	ll t=240-k;
	ll s,flag=0;
	for (ll i=n;i>0;i--)
	{
		s=5*i*(i+1)/2;
		if (s<=t && s<240)
		{
			cout<<i<<"\n";
			flag=1;
			break;
		}
	}
	if(flag==0)
		cout<<"0\n";
}

#include <bits/stdc++.h>

using namespace std;
int n, k ;
int main()
{
    cin >>n>>k;
    int time_left=240-k,nbr=0;
     for (int i =1 ; i<=n;i++)
     {
         time_left-=i*5;
         nbr++;
         if (time_left<0){
            nbr--;
            break;
         }
     }cout<<nbr;
     return 0 ;
}

#include<stdio.h>
int main()
{
int n,m;
scanf("%d",&n);
scanf("%d",&m);
int res=0;
int result=240-m;
int count=0;
for(int i=1;i<=n;i++)
{
res+=i*5;
if(res<=result)
{
count=count+1;

}
}
printf("%d",count);
}

#include <bits/stdc++.h>
using namespace std;
int main()
{
	int n,m;
	cin>>n>>m;
	int soat =240-m;
	int k=0;
	int s=0;
	for (int i=1;i<=n;i++)
	{
		s+=5*i;
		if (s<=soat)
		{
			k++;
		}
		else {
			break;
		}
	}
	cout <<k;
	return 0;
}

#include <iostream>
using namespace std;
int mas[11];
int main()
{
	int n, k;
	cin >> n >> k;
	int d = 0; //время на задачи
	int m = 0; //счетчик задач
	int a = 240 - k; //скока время нужно

	for (int i = 1; i <= n; i++) {
		d = d + 5 * i;
		m++;
	}

	if (a < d) {
		for (int j = m; j > 0; j--) {
			d = d - 5 * j;
			m--;
			if (a >= d) {
				break;
			}
		}
		cout << m;
	}
	else {
		cout << m;
	}
	return 0;
}

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string>
#include <vector>
#include <numeric>
#include <set>
#include <cmath>
#include <random>
#include <ctime>
#include <chrono>
#define INF ((unsigned) ~0)
#define DEBUG(x) cout << #x << " = " << x << '\n'
#define endl '\n'
using namespace std;
using namespace std::chrono;
int binarySearch(vector<int>, int);

int main() {
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	const int ct = 240;
	int n, k; cin >> n >> k;
	int tm = ct - k,
		q = 0,
		i = 1;
	while (tm > 0) {
		if (tm < (5*i) || i>n) break;
		tm -= (5 * i);
		q++;
		i++;
	}
	cout << q << endl;
}

int binarySearch(vector<int> a, int target) {
	int N = a.size(), L = 0, R = N - 1, mid = 0;
	while (L <= R) {
	mid = L + (R - L) / 2;
		if (a[mid] == target)
		{
			return mid;
		}
		if (a[mid] < target) {
			L = mid + 1;
		}
		else {
			R = mid - 1;
		}
	}
	return -1;
}

#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,m,i=1;
	scanf("%d%d",&n,&m);
	while(m+i*5<=240&&i<=n){
		m+=i*5;
		i++;
	}
	printf("%d",i-1);
}

// Example program
#include <iostream>
#include <string>
using namespace std;
int main()
{
    int n, t;
    cin >> n >> t;
    int k = 240 - t;
    int sum = 5, i = 1;
    if(k < 5)
    {
        cout << 0;
        return 0;
    }
    while(i < n && sum + (i + 1) * 5 <= k)
    {
        i++;
        sum += i * 5;
    }
    cout << i;
    return 0;
}

#include <iostream>
using namespace std;
int main()
{
	int number, minute, sum = 0,total=0;
	cin >> number >> minute;
	for (int c = 1; c <= number; c++){
		sum += 5;
		total += sum;
		if (total + minute > 240){
			cout << c - 1;
			break;
		}
		else if (c == number)cout << c;
	}
}

// Problem http://codeforces.com/problemset/problem/750/A
// Solution for, https://harun9009.wordpress.com/2017/08/28/codeforces-solution-750a-new-year-and-hurry/
// Language GNU G++ 5.1.0
#include<bits/stdc++.h>
#include<algorithm>
using namespace std;
int main()
{
 int n,k,i,minn=0;
 scanf("%d%d",&n,&k);
 for(i=1;i<=n;i++){
 minn+=i*5;
 if(minn>240-k){
 printf("%d\n",i-1);
 return 0;
 }
 }
 printf("%d\n",i-1);
 return 0;
}

#include <iostream>
#include <algorithm>
#include <string>
using namespace std;
#define ull unsigned long long
#define d digital

int main()
{
	int n, k;
	cin >> n >> k;
	int left = 240 - k;
	int i = 0, t = 0;
	while (i + 1 <= n && t + (i + 1) * 5 <= left) {
		i++;
		t += i * 5;
	}
	cout << i << endl;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int main()
{
	cin>>n>>k,k=(240-k)/5;
	for(int x=1;x<=n;x++)
		if(x*(x+1)/2>k){cout<<x-1;return 0;}
	cout<<n;
	return 0;
}

 #include<bits/stdc++.h>
    #include<algorithm>
    using namespace std;
    int main()
    {
        int n,k,i,minn=0;
        scanf("%d%d",&n,&k);
        for(i=1;i<=n;i++){
            minn+=i*5;
            if(minn>240-k){
                printf("%d\n",i-1);
                return 0;
            }
        }
        printf("%d\n",i-1);
        return 0;
    }

#include <cstdio>
int n,k,cur,cnt;
int main()
{
    scanf("%d%d",&n,&k);
    cur=240-k;
    for(int i=1;i<=n;i++)
    {
        int now=5*i;
        if(cur>=now) cur-=now,++cnt;
        else break;
    }
    printf("%d\n",cnt);
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
int s=4*60;
int main()
{
	int k,n,i;
	cin>>n>>k;
	s-=k;
	for(i=1;i<=n;i++)
	{
		s-=i*5;
		if(s<0)
		{
			cout<<i-1;
			return 0;
		}
	}
	cout<<n;
}

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

int main() {

	int n,k;
	cin>>n>>k;
	int a[n+1];
	int sum[n+1];
	a[0]=5;
	for(int i=1;i<n;i++){
	    a[i]=a[i-1]+5*(i+1);

	}
    /*for(int i=0;i<n;i++){cout<<a[i]<<" ";}
    cout<<endl;*/
	int key=240-k,l=0,h=n-1,res;
//	cout<<"key is "<<key<<endl;
    int i,f=0;
	for( i=0;i<n;i++){
	    if(key<a[i]){
	        f=1;cout<<i<<endl;
	        break;
	    }
	    if(a[i]==key){
	        f=1;cout<<i+1<<endl;
	        break;}
	}
	if(!f)
	cout<<n<<endl;

}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int ans=0;
int main()
{
    cin>>n>>k;
    k=240-k;
    for(int i=1;i<=n;i++)
    {
        if(5*i<=k)
        {
            k=k-(5*i);
            ans++;
        }
    }
    cout<<ans;
    return 0;
}

#include<bits/stdc++.h>
#define lb lower_bound
using namespace std;
int main()
{
    int n,k;cin>>n>>k;
    vector<int> v(n);v.at(0)=5;
    for(int i=1;i<n;i++) v.at(i)=(i+1)*5+v.at(i-1);
    int a=lb(v.begin(),v.end(),240-k)-v.begin();
    if(a==n)cout<<a;
    else if(v.at(a)==(240-k))cout<<a+1;
    else cout<<a;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,m,i,sum=0;
	cin>>n>>m;
	for(i=1;i<=n;i++){
        if(i*(i+1)*2.5+m>240){
			cout<<i-1;
			return 0;
		}
	}
    cout<<n;
	return 0;
}

#include<bits/stdc++.h>
#define lb lower_bound
using namespace std;
int main()
{
  int n,k;cin>>n>>k;
  vector<int> v(n);v.at(0)=5;
  for(int i=1;i<n;i++)v.at(i)=(5*(i+1))+v.at(i-1);
  int a=lb(v.begin(),v.end(),240-k)-v.begin();
  if(a==n) cout<<a;
  else if(v.at(a)==240-k)cout<<a+1;
  else cout<<a;
  return 0;
}

#include<cstdio>
using namespace std;
int main()
{
	int n,k;
	scanf("%d%d",&n,&k);
	k=240-k;
	int ans=0;
	for(int i=1;i<=n;i++)
	{
		if(5*i<=k)
		{
			k=k-5*i;
			ans++;
		}
	}
	printf("%d",ans);
	return 0;
}

#include<iostream>
using namespace std;
int main(){
	int a,n,k,sum=0,c=0;
	cin>>n>>k;
	a=240-k;
	for(int i=1;i<=n;i++){
		sum+=i*5;
		if(a>=sum)
			c++;
	}
	cout<<c<<endl;
    return 0;
}

//Wilson-judger-enable-o2
#include<bits/stdc++.h>
using namespace std;
unsigned int N,M,sum;
int main(void){
	scanf("%d%d",&N,&M);
	for (int i=1;i<=N;++i){
		sum+=i*5;
		if (sum+M>240){
			cout<<i-1;
			return 0;
		}
	}
	cout<<N;
	return 0;
}

#include<iostream>
#include<algorithm>
using namespace std;
int main()
{
    int n,k;
    cin>>n>>k;
    int rel=4*60-k;
    int ans=0;
    for(int i=1;i<=n;i++)
    {
        while(rel>=(ans+1)*5&&(ans+1)<=n)
        {
            ans++;
            rel-=ans*5;
            if(rel<=0)   break;
        }
    }
    cout<<ans<<endl;
    return 0;
}

#include<iostream>
using namespace std ;
int main ()
{
	int x , y , z , m ;
	cin>>x>>y;
	z=240-y;

	if(z<5)
		{
										m=0;
										if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
	else if (z<15 && z>=5)
		{
										m=1;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
		else if (z<30 && z>=15)
		{
										m=2;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
		else if (z<50 && z>=30)
		{
										m=3;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
			else if (z<75 && z>=50)
		{
										m=4;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
			else if (z<105 && z>=75)
		{
										m=5;
			                      if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
				else if (z<140 && z>=105)
		{
										m=6;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
				else if (z<180 && z>=140)
		{
										m=7;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}
					else if (z<225 && z>=180)
						{
							m=8;
				if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				}
					else if (z<275 && z>=225)
								{
									m=9;
		                             	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

					}

						else if (z<300 && z>=275)
		                  			{
										m=10;
			                        	if(m>x)
			                        	cout<<x<<endl;
										else
											cout<<m<<endl;

				                 	}

return 0 ;
}

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

int main()
{
    int n,k,tot=0,sheng;
    cin>>n>>k;
    sheng=240-k;
    for (int i=1;i<11;i++)
    {
        if ((5+5*i)*i/2<=sheng&&(5+5*(i+1))*(i+1)/2>sheng)
        {
            printf("%d\n",i);
            break;
        }
         if (i==n&&(5+5*i)*i/2<=sheng){
            printf("%d\n",i);
            break;
        }
        if (i==1&&sheng<5){
        	printf("0\n");
        	break;
		}
    }
    return 0;
}

#include<iostream>

using namespace std;

int cnt[15];
int main()
{
    int n,k;cin>>n>>k;
    int v = 240 - k;
    int s=0,l=0,h=n,i=0,mid;cnt[1]=5;
    for(int i=2;i<=n;i++)
        cnt[i]=cnt[i-1]+(i*5);

    while(l<h)
    {
        mid = (l+h+1)/2;// a = 5 10 15 , v =18

         if(cnt[mid]<=v)
            l=mid;
        else
            h=mid-1;

    }
    cout<<l;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;

int main ()
{
    scanf("%d%d",&n,&k);
    for(register int i=1;i<=n;i++)
        if(i*(i+1)*5/2+k>240)
		{
			printf("%d\n",i-1);
			return 0;
		}
    printf("%d\n",n);
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int main()
{
    cin>>n>>k;
    for(int x=1;x<=n;x++)
        if(x*(x+1)*2.5+k>240){cout<<x-1;return 0;}
    cout<<n;
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
int n,i,k,s=0;
cin>>n>>k;
k=240-k;
for(i=1;i<=n;i++)
{
  k=k-5*i;
    if(k<0)
    break;
        s++;}
    cout<<s;

}

#include<iostream>
using namespace std;
int main()
{
    int i=1,n,k,time;

    cin>>n;

    cin>>k;
    time=240-k;
    while(time>=0)
    {
        time=time-(5*i);
        i++;
    }
    if(i-2>=n){cout<<n;return 0;}
    cout<<i-2;
    return 0;
}

#include <iostream>
#include <stdio.h>

using namespace std;
   int a,b,i,k,n;
   bool m;
int main()
{
    cin >> n >>k;
    k = 240 - k;
    m = true;
for ( i = 1; i <= n; ) {
   a = i * 5;

if (a > k and m)
   {
      cout <<i-1<< endl;
      m = false;
   }
   else
    {
     k = k - a;
    }
   i++;
}
  if (m){
   cout<<n<< endl;
}
    return 0;
}

#include <stdio.h>
using namespace std;
int main()
{
    int n,k; scanf("%d %d",&n,&k);
    int h=240-k;
    for(int i=1; i<=n; i++)
    {
        if(i*5>h)
        {
            printf("%d",i-1);
            return 0;
        }
        h-=i*5;
    }
    printf("%d\n",n);
    return 0;
}

#include <iostream>
using namespace std;
int main(){
	int num, got,leftt;
	cin>>num>>got;
	leftt=240-got;
	int i=1;
	if(leftt==0){
		cout<<0;
	}
	else{
		for(i=1;leftt>=0;i++){
			leftt=leftt-5*i;
		}
		if(i-2>=num){
			cout<<num;
		}
		else cout<<i-2;
	}
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int main(){
    cin>>n>>k;
    for(int x=1;x<=n;x++)
        if(x*(x+1)*2.5+k>240){cout<<x-1;return 0;}
    cout<<n;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define vi vector<int>
#define mii map<int,int>
#define tests int t; cin>>t; while(t--)
#define M 1000000007
#define pb push_back
#define ff first
#define ss second
#define pii pair<int,int>

int32_t main()
{ ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int n,k;
    cin>>n>>k;
    int sum=0,i;
    for(i=1;i<=n;i++)
    {
        sum=sum+5*i;
        if(!((sum+k)<=240))
        {
            break;
        }
    }
    cout<<i-1;
}

#include <iostream>
using namespace std;
int main()
{
	int n, k;
	cin >> n >> k;
	for(int i = 1; i <= n; i++)
	{
		if(i * (i + 1) * 2.5 + k > 240)
		{
			cout << i - 1;
			return 0;
		}
	}
	cout << n << endl;
	return 0;
}

#include <iostream>
using namespace std;
int n, k, sum, res;
int main( ) {
	cin >> n >> k;
	res = 240 - k;
	for(int i = 1; i <= n + 10; i++) {
		sum += 5 * i;
		if(sum > res) {
			if(i - 1 > n) {
				cout << n;
			} else
			cout << i - 1;
			return 0;
		}
	}
	return 0;
}

#include <iostream>
using namespace std;
int n,k,a=0;
int main (){
    cin>>n>>k;
    int s=240-k;
    for(int i=0;i<=n;i++){
            int t=5*i*(i+1)/2;
    if(t<=s){
        a=i;
    }}
    cout<<a;
    return 0;}

#include <bits/stdc++.h>
using namespace std;
int t,mi,ti,i;
int main(){
cin>>ti>>t;
t=(240-t)/5;
for(i=ti;i>=0;i--){
	if((i*i+i)/2<=t) {
		cout<<i;
		return 0;
	}
}
return 0;
}

#include<iostream>
using namespace std;
int main(){
	long long  int n ,k ,t=0;
	cin>>n>>k;
	while(k <=240){
	t++;k += 5*t;
	}
	cout<<min(t-1,n);
}

#include <iostream>

using namespace std;

int main()
{
int x,y,ans=0,sum=0;
cin>>x>>y;
if(x>=y && x!=10)
{cout<<x;
    return 0;
}
if(x==10 && x>y)
{cout<<x-1;
    return 0;
}

ans=240-y;
for(int i=5;i<=ans&&sum<x;i+=5)
   {sum++;
    ans-=i;}
cout<<sum;

    return 0;
}

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<long long, long long> ii;
typedef vector<ii> vii;
typedef vector<ll> vi;
#define endl "\n"
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define FASTIO ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
void arrayIn(ll* A,ll n){ for ( ll K = 0; K < n; K++){ cin >> A[K]; } }
void arrayOut(ll* A,ll n){ for ( ll K = 0; K < n; K++){ cout << A[K]<<' '; } }
//declare variable----------------------------------------------------

//--------------------------------------------------------------------------
int main(){
    FASTIO;
    #ifndef ONLINE_JUDGE
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    #endif
    // CODE--------------------------------------------------------------
    int n,k;
    cin>>n>>k;
    for(int i=1;i<=n;i++){
        k=k+i*5;
        if(k>240){
            cout<<--i;
            return 0;
        }
    }
    cout<<n;
//---------------------------------------------------------------------
    return 0;
}

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

int main() {
	int n,k;
	cin>>n>>k;
	vector<int>q(n);
	q[0]=5;
	for(int i=1;i<n;++i){
		q[i]=q[i-1]+(i+1)*5;
	}
	int w=240-k;
	int res=0;
	for(int i=0;i<n;++i){
		if(q[i]>w){
			res=i;
			break;
		}
		if(q[i]==w){
			res=i+1;
			break;
		}
	}
	if(q[n-1]<w){
		cout<<n;
	}else{
		cout<<res;
	}
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int main(){
    scanf ("%d%d",&n,&k);
    k=240-k;
    int ans=0;
    for (int i=1;i<=n;i++)
        if (k<5*i) break;
        else k-=5*i,ans++;
    printf ("%d",ans);
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,k,i,hour,number;
    hour=240;
    number=0;
    cin>>n>>k;
    hour-=k;
    for(int i=1;i<=n;i++)
    {
        if(i*5<=hour)
        {
            hour-=i*5;
            number++;
        }
        else
            break;
    }
    cout<<number<<endl;
    return 0;
}

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int a,b;
int main()
{
    int ans;
    while(cin>>a>>b)
    {
        int tmp=240-b;
        if(tmp<5)
            ans=0;
        else
        {
            for(int i=1; i<=a; i++)
            {
                tmp-=i*5;
                if(tmp<(i+1)*5&&i+1<=a)
                {
                    ans=i;
                    break;
                }
                else if(tmp==(i+1)*5&&i+1<=a)
                {
                    ans=i+1;
                    break;
                }
                else if(i==a)
                    ans=i;

            }

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

#include<algorithm>
#include<iostream>
#include<string>
#include<vector>
#include<list>
#include<iomanip>
#include<cmath>
#include<stack>
#include<map>
#define ll unsigned long long
int sum(int k)
{
	if (k < 0)
		return 0;
	int t = 0;
	while (k)
	{
		t += 5 * k;
		k--;
	}
	return t;
}
using namespace std;

int main()
{
	int n, k;
	cin >> n >> k;
	int time = 240 - k;
	int i = 0;
	while (sum(i + 1) <= time)
		i++;
	cout << min(max(0,i),n) << endl;
	//system("pause");
	return 0;
}

#include<algorithm>
#include<iostream>
#include<string>
#include<vector>
#include<list>
#include<iomanip>
#include<cmath>
#include<stack>
#include<map>
#define ll unsigned long long
int sum(int k)
{
	if (k < 0)
		return 0;
	int t = 0;
	while (k)
	{
		t += 5 * k;
		k--;
	}
	return t;
}
using namespace std;

int main()
{
	int n, k;
	cin >> n >> k;
	int time = 240 - k;
	int i = n/2;
	if(sum(i) <= time)
	{
		while(sum(i+1) <= time && i <= n)
			i++;

	}
	else
	{
		while (sum(i)> time && i >= 0)
		{
			i--;
		}

	}
	cout << min(max(0,i),n) << endl;
	//system("pause");
	return 0;
}

#include<iostream>
#include<string.h>
#include<iomanip>
#include<math.h>

using namespace std;
int main()

				{ int n,k,a,b;
				  cin>>n>>k;
				  k=240-k;

				  for(int i=1;;i++)
				  {a=(i*(10+((i-1)*5)))/2;

				   if(k<5){b=0;break;
				  }
				  else{
				  if(a>k){b=i-1;break; }
				  else{if(a==k){b=i;break;
				  }}
				   }}

				  if(b<=n){cout<<b;}
				  else{cout<<n;  }}

#include <iostream>

using namespace std;
int n,k,l,r,mid;

int main()
{
    cin >> n >> k;
    if(n==k && k==1)
    {
        cout << 1;
        return 0;
    }
    if(k>=236)
    {
        cout << 0;
        return 0;
    }
    if(n==1 && k<=235)
    {
        cout << 1;
        return 0;
    }
    l=1;
    r=n;
    while(l!=r)
    {
        mid=(l+r+1)/2;
        if(5*mid*(mid+1)/2>240-k)
            r=mid-1;
        else
            l=mid;
    }
    if(5*mid*(mid+1)/2>240-k)
        cout << mid-1;
    else
        cout << mid;
    return 0;
}

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

int main(){
    int n,k;cin>>n>>k;
    int a[n];
    a[0]=5;
    for(int i=1;i<n;i++){
        a[i]=5*(i+1)+a[i-1];
    }
    k=240-k;
    if(k<=0){
        puts("0");
        return 0;
    }
    int l=-1,h=n-1;
    while(l<h){
        int mid=(l+h+1)/2;
        if(a[mid]<=k)
            l=mid;
        else
            h=mid-1;
    }
    cout<<l+1<<endl;

    return 0;
}

#include <iostream>
using namespace std;

int calculate(int n){
  int sum = 0;
  for(int i = 1; i <= n; i++){
	sum += i * 5;
  }
  return sum;
}

int main(void){

  int n, k, sum, a;
  cin >> n >> k;
  for(int i = n; i >= 0; i--){
  	sum = 0;
  	sum = calculate(i) + k;
  	if(sum <= 240){
  		a = i; break;
	  }
  }
  cout << a;
}

#include <iostream>

using namespace std;
short n,k,i;
int main()
{
    cin>>n>>k;
    for(i=1;i<=n;++i)
        if(5*(i*i+i)/2+k>240)
            break;
    cout<<i-1;
    return 0;
}

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

int main(int argc, char *argv[])
{
    int n,k,t=240,v=0;
    cin>>n>>k;
    if(t-k<5)
    cout <<0;
    else {
    t-=k;
    for(int i=1;i<=n;i++)
    {
         t-=(i*5);
         v+=(i*5);
         if(t<0)
         {cout<<i-1;return 0;}
         if(t<5)
         {cout<<i;return 0;}
    }
            cout<<n;

    return EXIT_SUCCESS;}
}

#include<iostream>
using namespace std;
int main(void){
int a,b,k=0;
	cin>>a>>b;
while(b<=240)k++,b+=5*k;
cout<<min(k-1,a);
return 0;
	}

#include<bits/stdc++.h>
using namespace std;
int main()
{
   int a,b,i=0;
   cin>>a>>b;
   while(b<=240)
   {
      i++;
      b+=i*5;
   }
   cout<<min(i-1,a);
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int np,oprt,temp,temp2;
    cin>>np>>oprt;

    temp=240-oprt;

    temp2=((np*(np+1))/2)*5;

    for(int w=np;w>=0;w--,np--)
    {
        if(oprt==240)
        {cout<<0;break;}

        else if(temp2 <= temp)
        {cout<<np;break;}

         temp2-=np*5;
    }

    return 0;
}

#include <iostream>

using namespace std;

int main()
{
    int n,k,left_time,problems_solved=0;
    cin>>n>>k;
    left_time=240-k;
    int i=1;int sum=0;
    while(i<=n)
    {
        //cout<<"before entering"<<i<<endl;
        sum+=i*5;
        //cout<<sum<<endl;
        if(sum<=left_time)
          {
              problems_solved=i;

          }
          i++;

    }
        cout<<problems_solved<<endl;

    return 0;
}

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n,k;
    cin>>n>>k;
    int c=0;
    k=240-k;
    for(int i=1;i<=n;i++)
    {
        k-=(5*i);
        if(k<0) break;
        c++;
    }
    cout<<c<<"\n";
    return 0;
}

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

int main() {
	int time = 4 * 60;
	int n, k;
	cin >> n >> k;
	time -= k;
	int ans = n;
	for (int i = 1; i <= n; i++) {
		if (i * 5 > time) { ans = i - 1; break; }
		else time -= i * 5;
	}
	cout << ans;
}

#include<stdio.h>
int main()
{
	int n,k,yushu,i;
	scanf("%d %d",&n,&k);
	yushu=240-k;
	i=1;
	while (i<=n&&yushu/(i*5)>0){
		yushu=yushu-i*5;
		i=i+1;
	}
	printf ("%d\n",i-1);
	return 0;
}

#include <cstdio>
int main(){
	int k,n,problems=0,time=0;
	scanf("%d %d",&n,&k);
	for(int i=1; i<=n; i++){
		time+=5*i;
		if(240-time>=k) problems++;
	}
	printf("%d",problems);
}

#include <iostream>

using namespace std;

int main()
{
    int n,k,counter=0;
    int sum=0;
    int product=1;
    int sum2=0;

    int x;
    cin>>n>>k;
    x=(240-k);

for(int i=1;i<=n;i++)
{
    sum2=sum2+i;
}
if(k==240)
    cout<<0;
  else if(sum2*5<=x)
    cout<<n;
 else
    {

    for(int i=1;i<=n;i++)
     {
         product=i*5;
         sum=sum+product;
         counter++;
         if(sum>x)
            break;

     }
     cout<<counter-1;}

    }

#include<bits/stdc++.h>
#define ll long long int
using namespace std;
int main(void)
{
    ll i , n, j , k, l , counter = 0  ;

    cin >> n >> k;

    if( k >= 236 )
    {
        cout << 0 <<endl;
        return 0;
    }

    ll a = 240 - k ;

    ll ans = a / 5 ;
    ll sum = 0;
    counter  = 0;
    for( i = 5; i<=a ; i+=5)
    {
        sum+=i ;
        counter++;
        if(sum==a)
        {
            if(counter > n)
            {
              cout << n <<endl;
            }
            else
            {
                  cout << counter <<endl;
            }

            break;
        }
        else if(sum > a)
        {
            if(counter > n)
            {
              cout << n <<endl;
            }
            else
            {
                  cout << counter - 1 <<endl;
            }
            break;
        }
    }

}

#include <iostream>
using namespace std;
int main(){
	int n, k;
	int i=1;
	cin>>n>>k;
	int t=240-k;
	t-=5*1;
	while(t-5*i>0){
		if(n==1)
			break;
		i++;
		t-=5*i;
		if(i==n){
			break;
		}
	}
	if(t<0)
		i--;
	cout<<i<<endl;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n,k,last=240;
	cin>>n>>k;
	last-=k;
	for(int i=1;i<=n;i++)
	{
		last-=5*i;
		if(last<0)
		{
			cout<<i-1<<endl;
			return 0;
		}
	}
	cout<<n<<endl;
	return 0;
}

#include <iostream>
#include <cstdlib>
#include <cmath>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
	int n,k,t=0;
	cin>>n>>k;
	int min=240;
	min-=k;
	if (min<=0)
	{
		cout<<0<<endl;
		return 0;
	}
	for (int i=1;i<=n;i++)
	{
		if (min-i*5<0) break;
		min-=i*5;
		t=i;
	}
    cout<<t<<endl;
	return 0;
}

//#include "pch.h"
#include <iostream>
using namespace std;

int main()
{
	int n, t, T, i = 0;
	cin >> n >> t;
	T = 240 - t;
	while (T >= 5 * (i + 1)) {
		T -= 5 * i;
		if (T >= 5 * (i + 1))
			i++;
	}
	if (i >= n)
		cout << n;
	else
		cout << i;
}

#include<bits/stdc++.h>
using namespace std;
int n,k;
int ans;
int main(){
	scanf("%d%d",&n,&k);
	k=240-k;
	for(int i=1;i<=n;i++){
		k-=i*5;
		if(k<0) break;
		ans++;
	}
	printf("%d",ans);

	return 0;
}

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

using namespace std;

int  sum = 0,ans = 0;

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

	ans = 1440 - k;
	for (int i = 1; i <= n; ++i)
	{
		//cout << ans << "\n";
		if (ans - (5 * i) < 1200){
			cout << sum;
			return 0;
		}
		else if (ans - (5 * i) == 1200)
		{
			cout << sum + 1;
			return 0;
		}
		ans = ans  -  (5 * i);
		++sum;
		if (i == n ){
			cout <<sum;
			return 0;
		}
	}
}

#include <iostream>
using namespace std;

int n, k, t = 0;

int main() {
    cin >> k >> n;
    n = (240-n)/5;
    while ((t*t+3*t+2)/2 <= n && t < k) t++;
    cout << t;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int a,b;

    cin>>a>>b;
    int i;
    for(i= 1; i<=a;i++){
        b += i*5;
        if (b>240) {
            break;
        }
    }
    cout<<i-1;
}

#include <iostream>
using namespace std;
int n,k;
int main(){
	cin>>n>>k;
	int t=240,i=5,j=0;
	t-=k;
	while(t>0){
		t-=i;
		i+=5;
		j++;
		if(t<0){
			j--;
			break;
		}
		if(j==n)
			break;
	}
	cout<<j<<endl;
//	system("pause");
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int n,k,s;
int main()
{
cin>>n>>k;
s+=k;
for(int i=1;i<=n;i++)
{
s+=i*5;
if(s>240)
{
cout<<i-1;
return 0;
}
}
cout<<n;
}

#include<iostream>

using namespace std;

int main(){
	int sum=0;
	int k,i,n;
	cin>>n>>k;
	if(k>=240) cout<<0;
	else {
		for(i=1;i<=n;i++){
			sum+=5*i;
			if(sum+k>240) break;
		}
		cout<<(i-1);
	}
}

#include <iostream>

using namespace std;

int main()
{
    int n,k;
    int time=240;
    cin>>n>>k;
    time-=k;
    int i=0;
    for(i=0;i<n;i++)
    {
        if(time-5*(i+1)>=0)
            time-=5*(i+1);
        else
            break;
    }
    cout<<i<<endl;
    return 0;
}

#include <iostream>

using namespace std;

int time = 240, n, k, ZadTime = 0;

int main()
{

    cin >> n; cin >> k;
    time -= k;
    for (int i = 1; i <= n; i++)
        ZadTime += i * 5;

    int i = n;
    while (true)
    {
       if (ZadTime <= time) break;

       ZadTime -= 5 * i;
       i--;
    }

   /* i = 1;
    while (i < n)
    {
        if (ZadTime = 0) break;
        ZadTime -= i * 5;
        i++;
    }*/

    cout << i << endl;

    return 0;
}

#include<cstdio>
#include<iostream>
using namespace std;
int n,k;
int main(){
    cin>>n>>k;
    k=240-k;
    for(int i=1;i<=n;i++)
    {
        if(i*5>k)
        {
            cout<<i-1<<endl;
            return 0;
        }
        k-=i*5;
    }
    cout<<n<<endl;
    return 0;
}

#include"stdio.h"

int main()
{
	int n, k;
	scanf("%d", &n);
	scanf("%d", &k);
	int timedu = 240 - k;
	int dembai = 0;
	int i = 1;
	while (timedu > 0 && dembai < n)
	{
		timedu -= i * 5;
		i++;
		dembai++;
	}
	if (timedu < 0)
		dembai--;
	printf("%d", dembai);
}

#include <bits/stdc++.h>
using namespace std;
int n,k,kq,f[17];
int main()
{
    //freopen("b1.inp","r",stdin);
    //freopen("b1.out","w",stdout);
    cin>>n>>k;k=(240-k)/5;
    f[0]=0;
    for (int i=1;i<=10;i++) f[i]=f[i-1]+i;
    int d=0,c=10;kq=0;
    while (d<=c){
        int g=(d+c)/2;
        if (f[g]<=k){kq=g;d=g+1;}
        else c=g-1;
    }
    cout<<min(kq,n);
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
	int n,k,res=0;
	cin >> n >> k;
	int diff=240-k;
	vector <int> arr(n);
	arr[0]=5;
	for(int i=1;i<n;i++){
		arr[i]=5*(i+1) + arr[i-1];
	}
	res=upper_bound(arr.begin(),arr.end(),diff)-arr.begin();
	cout << res << endl;
}

#include<bits/stdc++.h>
using namespace std;
int n,f,i;
int main()
{
	cin>>n>>f;
	f=(240-f)/5;
	for(i=1;i<=n;i++)
  	{
  		f=f-i;
	   if(f<0)
	   {
	   	break;
	   }
  	}
	cout<<i-1;
	return 0;
	}

#include<iostream>
using namespace std;
int main(){
    int n,k,i;
    cin>>n>>k;
    k=240-k;
    for(i=1;i<=n;i++){
        k-=i*5;
        if(k<0)break;
    }
    cout<<i-1;
    return 0;
}

#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main(){
   ll n,k,sum=0,c=0;
   cin>>n>>k;
   ll rem=240-k;
   for(int i=1;i<=n;i++)
   {
       sum+=5*i;
       if(sum>rem) break;
       c++;
   }
   cout<<c<<endl;
}

//
//  main.cpp
//  codeforces
//
//  Created by Anthony Molyviatis on 4/12/17.
//  Copyright © 2017 Xelor. All rights reserved.
//

#include <iostream>

using namespace std;

int main() {

    int n, k;
    int count = 5;
    cin >> n >> k;

    int remainder = 240;
    while ( n != 0 && (remainder - k) - count >= 0){
        remainder -= count;
        count += 5;
        n--;
        cout << remainder << endl;
    }
    cout << (count/5) - 1 ;

    return 0;
}

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

int main() {
	// your code goes here
	int n,k;
	cin >> n >> k;
	int v[10];
	v[0] = 5;
	for(int i = 1 ; i < n ; i++)
	{
		int t = v[i-1]+(i+1)*5;
		v[i] = t;
	}
	int tot=240,rem=tot-k,l=0,h=n-1,mid,ans=0;
//	cout << nk << " " << rem << '\n' ;
	if(n == 1 && k < 240){
		cout << 1 << endl;
		return 0;
	}
	if(n == 1 && k > 240){
		cout << 0 << endl;
		return 0;
	}
	while(l <= h)
	{
		mid = (l+h)/2;
		if(v[mid] <= rem)
		{
			ans = mid+1;
			l = mid+1;
		}
		else
		h = mid-1;
	}
	cout << ans << endl;
	return 0;
}

#include <iostream>
using namespace std;

int main()
{
    int n, m;
    cin>>n>>m;
    int left = 240 - m;
    int answer = 0;
    for(int i = 1; i < n; i++){
        if(left>=0){
            left  = left - i*5;
        }
        if(left == 0){
            answer = i;
            break;
        }
        if(left<0){
            answer = i-1;
            break;
        }
        if(i=n-1){
            answer = m;
            break;
        }
    }
    cout<<answer;
    return 0;
}

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

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

    int n, k;
    int time = 240;

    cin >> n >> k;

    time -= k;

    for (int i = 1; i <= n; ++i) {
        time -= i*5;

        if (time <= 0)
        {
            cout << i - 1;
            return 0;
        }
    }

    cout << n;

    return 0;
}

#include <iostream>

using namespace std;

int n, k, sum;

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

	for(int i=1; i <= n; i++) {
		sum += 5;
		if(sum + (i+1)*5 + k > 240) {
			cout << i;
			return 0;
		}
	}
	cout << n;
}

#include <iostream>
using namespace std;
int main ()
{
    int n,k,ile_spr(0);
    cin >> n >> k;
    for(int i=0; i<n; i++){
        int d;
        d+=5;
        ile_spr+=d;
    }
if(ile_spr+k<=240) cout << n;
  else {
        while(ile_spr+k>240){
            ile_spr-=5;
            n--;
    cout << n;
            return 0;
        }
    }
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

#define mp make_pair
#define all(x) (x).begin(), (x).end()
#define ldb ldouble
#define szz(x) (int)(x).size()
#define repi(i, p, n) for(int i=p;i<n;i++)
#define repl(i, p, n) for(ll i=p;i<n;i++)
#define Se second
#define Fi first
#define C(x) cout<<x;
#define Ex(x) return x;

typedef tuple <int, int, int> t3;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
typedef pair <ll, int> pli;
typedef pair <db, db> pdd;

//ll Min=1000000000000000000;
//ll Max=-Min;

int main()
{
    ll n,k,l=0;
    cin>>n>>k;
    k=240-k;
    while(k-l*5>-1)
    {
        l++;
        k-=l*5;
    }
    C(l);
    Ex(0);
}

#include<iostream>
using namespace std;
int main()
{
    int n,k,i=0;
    cin>>n;
    cin>>k;
    if(n<=10&&n>=1)
    {

    int rt,tt=0;
    rt=240-k;
    if(rt<5)
    {
        cout<<"0";return 0;
    }
    for(i=0;i<n&&tt<=rt;)
    {i++;tt=tt+5*i;}
    cout<<i-1;
    }
    return 0;

}

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,k,i,s=240;
    cin>>n>>k;
    s=-k;
    for( i=0;i<n;i++){
        s=-5*i;
        if(s<0){
            break;
        }
    }
    cout<<i<<endl;
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
ll n, k, dk, gecen;

int main(){
  ios_base::sync_with_stdio(false);
  cin.tie(NULL); cout.tie(NULL);
 // freopen("out.txt","r",stdin);
 // freopen("in.txt","w",stdout);
  cin >> n >> k;
  dk = 240-k;
  for(ll i=1; i<=n ;i++){
    gecen += i*5;
    if(gecen > dk){
      cout << i-1 << endl;
      return 0;
    }
  }
}

#include<bits/stdc++.h>
#define _ ios_base::sync_with_stdio(0);
#define du 240

using namespace std;

int n, t, k;

int main(){_
	cin >> n >> t;
	t=du-t;

	for(int i=5; i<t; i+=5, k++);

	cout << min(n, k-1) << endl;
	return 0;
}
// 1486828196138

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,k,rem,i,ans=0;
    cin>>n>>k;

    rem=240-k;
    for( i=1; i<=n && rem> 5 ; i++)
    {
       if((rem-(5*i))>=0){rem=rem-(i*5);
       ans++;}

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

//Bao
#include <bits/stdc++.h>

using namespace std;

long long n,w,k;

int main(){
    cin >> n >> k;
    w = (240 - k) * 2 /5;
    w = sqrt(w); cout << min(n,w);
}

#include<iostream>
using namespace std;
int main()
{   int n,k,a=0,b=0,c=0,d=0;
    cin>>n>>k;
    a=4*60;
    b=a-k;
    for(int i=1;i<=b;i++){
        c+=i*5;
        if(b<c){cout<<d;break;}
        d++;}
}

#include <iostream>

using namespace std;
#include  <string>
int main()
{
    int j,i,n,k;
    i=0;
    j=1;
    cin>> n >> k;
    while (i<=4*60-k && j<= n){
        i=5*j+i;
        j++;
    }
    cout<< j-1;
    return 0;
}

#include <iostream>
#include <time.h>
#include <vector>
using namespace std;

typedef long long int ll;
typedef unsigned long long int ull;

#define IN_OUT {freopen("in.txt", "r", stdin); freopen("out.txt", "w", stdout);}
#define FAST ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

clock_t startTime;
void getCurrentTime() {printf("%lf", (double)(clock()-startTime)/CLOCKS_PER_SEC);}

int binary(int ara[], int n, int item) {
	int left=1, right=n, mid=left+(right-left)/2;

	if(item < ara[1]) return -1;
	else if(item > ara[n]) return n;

	while(left < right) {
		if(item==ara[left]) return left;
		if(item==ara[right]) return right;
		if(ara[mid]==item) return mid;

		if(right-left==2) {
			//in next operation: mid=left+1, right=mid+1
			if(ara[left+1]<=item) return left+1;
			else if(ara[left+1]>item) return left;
			else return left+1;
		}

		if(item > ara[mid]) left = mid+1;
		else right = mid - 1;
		mid = left+(right-left)/2;

		if(left==mid && ara[mid]!=item) return left;
		if(right==mid && ara[mid]!=item) return right-1;
	}

	return 0; //just syntax. value has been returned in loop
}

int main() {
	// startTime = clock();
	// IN_OUT
	FAST

	int n, k, i;
	cin >> n >> k;
	int ara[n+1];

	ara[0] = 0;
	for(i=1; i<=n; i++) {
		ara[i] = i*5 + ara[i-1];
	}

	cout << binary(ara, n, 240-k) << "\n";

	// getCurrentTime();
}

#include <iostream>
using namespace std;
int main()
{
	int number, minute, c;
	cin >> number >> minute;
	minute = 240 - minute;
	for (c = 1; c <= number; c++){
		minute -= (c * 5);
		if (minute < (c + 1) * 5)
			number = 0;
	}
	if (c>number)cout << c - 1;
	else cout << c;
}

#include <iostream>
using namespace std;

int search_array(int arr[10], int n, int x){
    for(int i = 0; i < n; i++){
        if(arr[i] == x){
            return i+1;
        }
        else{
            if(x < arr[i+1] && x > arr[i]){
                return i+1;
            }
        }
    }
}

int main()
{
int n, minutes;
int mArr[10];

cin>>n>>minutes;

int maxSolvingTime = 240 - minutes;
int sub_total = 0;
for(int i = 0; i < n; i++){
    mArr[i] = (5*(i+1)) + sub_total;
    sub_total = mArr[i];
}
cout<<search_array(mArr, n, maxSolvingTime);

return 0;
}

#include <bits/stdc++.h>
using namespace std;
int n,k,kq,f[17];
int main()
{
    //freopen("b1.inp","r",stdin);
    //freopen("b1.out","w",stdout);
    cin>>n>>k;k=(240-k)/5;
    f[0]=0;
    for (int i=1;i<=10;i++) f[i]=f[i-1]+i;
    kq=lower_bound(f,f+10,k)-f;
    cout<<min(kq,n);
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
    unsigned int prob, party,left,left_now,i;
    cin>>prob;
    cin>>party;
    left = 240-party;
    if (left>0){
        for(i=1;i<prob;i++)
    {
        left_now = left - 5*i;
        if(left_now<5*(i))
        break;
    }

        cout<<i;
    }

    return 0;
}

#include<iostream>
#include<string>
#include<map>
#include<set>
#include<algorithm>
#include<vector>
#include<iomanip>
#include<deque>
using namespace std;
typedef long long int ll;
int main() {
	int n, k, c = 0, m;
	cin >> n >> k;
	m = 240 - k;
	if (m < 5)
		cout << 0 << endl;
	else
		for (int i = 1; i <= n; i++)
			if ((i*(1 + i) / 2) * 5 <= m)
				c++;
	cout << c << endl;

	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int i,j,k,n,m,t=0;
    cin>>m>>n;
    k=240-n;
   // cout<<(240-n)/5;
    while(k>0)
    {
         t++;
        k=k-5*t;
    }
    t--;
    if(t>m)
    {
        cout<<m;
    }
    else
        {
            cout<<t;
        }
}

#include <bits/stdc++.h>

using namespace std;
int n,k,s;
int main()
{
    cin>>n>>k;
    int d=1,c=n,kq,g;
    while (d<=c)
    {
        g=(d+c)/2;
        int sn=g/2*(10+(g-1)*5);
        //cout<<g<<" "<<sn<<endl;
        if (sn<=240-k) kq=g,d=g+1;
        else c=g-1;
    }
    cout<<kq;
}

#include <iostream>
using namespace std;
int main ()
{
    int n,k,ile_spr(0);
    cin >> n >> k;
    for(int i=0; i<n; i++){
        int d;
        d+=5;
        ile_spr+=d;
    }
if(ile_spr+k<=240) cout << n;
  else {
        while(ile_spr+k>240){
            ile_spr-=5;
            n--;
    cout << n;
            return 0;
        }
    }
    return 0;
}

#include<stdio.h>
int main()
{
    int n,k,i;
    scanf("%d %d",&n,&k);
    int sum=k,cnt=0,m;
    for(i=1;i<=n;i++){
       m=i*5;
        sum=sum+m;
        cnt++;
        while(sum<=240){
            break;
        }

    }
    printf("%d\n",cnt);

}

#include<bits/stdc++.h>
using namespace std;
int main()

{
	long long n,k;
	cin>>n>>k;
	vector<int>g(n);
	long long prev=0,i;
	for(i=1;i<=n;i++)
	{
		g[i-1]=5*i+prev;
		prev=g[i-1];
	}
	long long d=240-k;
	if(d>=g[n-1])
	{
		cout<<n<<"\n";
	}
	else
	{
		cout<< (upper_bound(g.begin(),g.end(),d)-g.begin())-1<<"\n";
	}
	return 0;
}

#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define fst first
#define sec second

using namespace std;
using ll = long long;

const int T = 240;
int a[11];

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

    int n, k; cin >> n >> k;
    for (int i = 0; i < n; ++i) {
        int temp = 5 * (i + 1);
        if (i == 0) a[i] = temp;
        else a[i] = temp + a[i - 1];
    }
    int l = 0, r = n - 1, mid = (l + r) / 2;
    while (l != r) {
        a[mid] > (T - k) ? r = mid - 1 : l = mid;
        mid = (l + r + 1) / 2;
    }
    cout << mid + (T - k > 5) << endl;

    return 0;
}

#include <iostream>
using namespace std;
int main()
{
    int a,b,i,m,c=0,sum=0;

    cin>>a>>b;

    m=240-b;
    for(i=1;i<=a;i++)
    {

       //cout<<"tt";
        c=i*5;
        sum+=c;
       // cout<<"yy"<<sum;
        if(sum>m)
        {
            cout<<i-1;break;
        }else if(sum==m)
        {
            cout<<i;break;
        }

    }
    return 0;
}

#include <cstdio>
int n,k,cur,cnt;
int main()
{
	scanf("%d%d",&n,&k);
	cur=240-k;
	for(int i=1;i<=n;i++)
	{
		int now=5*i;
		if(cur>now) cur-=now,++cnt;
		else break;
	}
	printf("%d\n",cnt);
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int i=0, j, k=0, n, m, sum=0, rest;
    cin >> n >> m;
    rest=240-m;
    while(k<=rest)
    {
         if(i==n || (sum > rest)) {

                break;
        }
        i++;
        sum+=(5*i);
        k=sum+(5*(i+1));
    }
    cout << i;

}

#include<bits/stdc++.h>

using namespace std;
int main()
{
    int j,c=0,i=0,y,k=0,m;

    cin>>y;
    cin>>m;

       for(i=0;i<m;i++){
      for(j=1;j<=y;j++){
        c=5*j;
        k=k+c;
       }
       if(240>=(m+k)){
        cout<<y;
        break;
       }
       else {
            k=0;
       c=0;
        y=y-1;
       }

   }

}

#include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <string>
#define MAX(x, y) (((x) < (y)) ? (y) : (x))
#define MIN(x, y) (((x) < (y)) ? (x) : (y))
typedef long long ll;
typedef unsigned char byte;

#define MAXN 1
#define MAXM 1

int main()
{

	return 0;
}

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

int main() {
	long long int n,k,m,c;
	cin>>n;
	cin>>m;
	c=240-m;
	k=c%5;
	c=c-k;

	vector<long long int>a;
	for(long long int i=0;i<=n;i++)
	{
	    a.push_back(i*5);

	}
	for(long long int i=1;i<=n;i++)
	{
	    a[i]=a[i]+a[i-1];
	}

	if(c>a[n])
	{
	    cout<<n;
	}
	else{
     for(long long int i=0;i<=n;i++)
     {
         if(c==k)
         {cout<<i;
             break;
         }
     }
	}

	return 0;
}

#include<stdio.h>
int main()
{
    int n,k,i=0,time1=0;
    scanf("%d%d",&n,&k);
    int time=240-k;
    while(1)
    {
      i++;
      if(i==n)
      break;
      time1=time1+i*5;
      if(time1>time)
      break;

    }
    printf("%d",i-1);
}

#include<bits/stdc++.h>
#include<algorithm>
using namespace std;
int main()
{
 int n = 0;
 int k,i,minn=0;
 scanf("%d%d",&n,&k);
 //printf("%d\n",n);
 int mi=0,ma=n;
 if(240-k<5){
 	printf("%d\n",i);
 	return 0;
 }
 while(mi<ma){
 	i = (ma+mi)/2;
 	int aux = 5*(i+1)* (double) (i/2.0);
 	int aux2 = 5*(i+2)* (double) ((i+1.0)/2);
 	int aux3 = 5*(i)* (double) ((i-1)/2);
 	//printf("%d %d %d\n",i,aux,aux2);
 	if((aux<=240-k && aux2>=240-k)){
 		if(aux==aux2){
 			printf("%d\n",i);
 			return 0;
 		}
 		if(aux2==240-k){
 			printf("%d\n",i+1);
			return 0;
 		}
 		printf("%d\n",i);
		 return 0;
 	}
 	else if(aux<=240-k){
 		mi = i+1;
 	}else{
 		ma = i-1;
 	}
 }
 printf("%d\n",i+1);
}

#include "bits/stdc++.h"
#define F first
#define S second
//#define B break
#define E exit(0)
#define endl '\n'
#define ccon continue
#define ins insert
#define rev reverse
#define pb push_back
#define pf push_front
#define ppf pop_front
#define ppb pop_back
#define sza(s) (int)(sz(s) - 1)
#define sz(s) (int)(s.size())
#define lb lower_bound()
#define ub upper_bound()
#define mkp make_pair
#define all(v) v.begin(), v.end()
#define whole(a,x) a + 1, a + x + 1
#define rall(v) v.rbegin(), v.rend()
#define out(v) copy(all(v),ostream_iterator<int>(cout," "));
#define cube(x) ((x)*(x)*(x))
#define SM(n) ((n) * (n + 1) / 2)
#define gcd __gcd
#define lcm(a,b) ((a) / gcd(a,b) * (b))
#define so(v, x) accumulate(all(v), x)
#define so2(v, x) accumulate(all(v), x, std::multiplies<int>())
#define so3(v, x) accumulate(them(v), x)
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
using ll = long long;
using ld = long double;
// COPIED BY |3-|\|-|3
#define IOS ios_base::sync_with_stdio(NULL);cin.tie (nullptr);cout.tie (nullptr);
using namespace std;
using si = set<int>;
using msi = multiset<int>;
using usi = unordered_set<int>;
using vi = vector<int>;
using vs = vector<string>;
using vpis = vector<pair<int,string>>;
using vpii = vector<pair<int,int>>;
using pii = pair<int,int>;
using pis = pair<int,string>;
using mii = map<int,int>;
using umii = unordered_map<int,int>;
using mib = map<int,bool>;
using mic = map<int,char>;
using mpsi = map<string,int>;
using mis = map<int,string>;
#define QR quartet
#define u_map unordered_map
const int MyIQ = 1e18 * 0 - 7;
const int E3 = 1e3 + 7;
const int E4 = 1e4 + 7;
const int E5 = 1e5 + 7;
const int E6 = 1e6 + 7;
const int E8 = 1e8 + 7;
const int MOD = 1e9 + 7;
const long long INF = 1e18 + 7;
const int nbI[] = {(-1), (+1), (0), (0), (+1), (+1), (-1), (-1)};
const int nbJ[] = {(0), (0), (+1), (-1), (+1), (-1), (+1), (-1)};
inline void setpr(int a,double b){cout<<fixed<<setprecision(a)<<b;}
inline int fact(int n){int sum=1;for(int i=2;i<=n;i++){sum*=i;}return sum;}
inline bool prime(int n){for(int i=2;i<=sqrt(n);i++){if(n%i==0){return 0;}}return(n==1?0:1);}
inline int pow(int a,int b){int res=1;while(b){if(b&1)res*=a;a*=a;b>>=1;}return res;}
string ALS="abcdefghijklmnopqrstuvwxyz";
string ALNS="qwertyuiopasdfghjklzxcvbnm";
string YN(bool i){return (i?"YES\n":"NO\n");}
#define int long long
int t;
void KOD () {
	t=1;
	while (t--) {
	int n, k; cin>>n>>k;
	int time = 240 - k;
	int i=1;
	for(i=1;i<=n;i++)
	{
		if((time - (5*i))>0)
			time -= 5*i;
		else
			break;
	}
	cout << i;
	}
	return;
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
KOD();
return 0;
}

#include <iostream>
#include <math.h>

using namespace std;

int main()
{
    int n,k,i=0,i1=1,a;
    cin>>n>>k;
    a=240-k;
    while(a>0){
        a=a-5*i1;
        i1++;
        i++;
    }
    if(a<0){
        if(i-1 >=n){
            cout<<n;
            return 0;
        }
        cout << i-1<<"";
    }
    else
        cout<<i;
    return 0;
}

#include <iostream>
using namespace std;
int main ()
{
    int n,k,ile_spr(0);
    cin >> n >> k;
    for(int i=0; i<n; i++){
        int d;
        d+=5;
        ile_spr+=d;
    }
if(ile_spr+k<=240) cout << n;
  else {
        while(ile_spr+k>=240){
            ile_spr-=5;
            n--;
    cout << n;
            return 0;
        }
    }
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

int n, k;

int f(int m) {
    int time = 240 - k, stime = 0;
    for (int i = 1; i <= m; i++) {
        stime += (5*i);
    }
    if(m == n && time - stime > 5) {
        return 1;
    }
    if ((time - stime) < 10) {
        return 1;
    } else return 0;
}

int main() {
    cin >> n >> k;
    for (int i = 1; i <= n; i++) {
        if (f(i)) {
            cout << i << endl;
            break;
        }
    }

    return 0;
}

    #include<bits/stdc++.h>
    using namespace std;
    int main(){
        int n,k;
        int trem = 240 - k;
        int a[n+1];
        int i;
        a[0]  = 0;
        for(i=1;i<=n;i++){
            a[i] = a[i-1]+5*i;
            }
            i=1;
        while(a[i]<=trem){
            i++;
        }
        cout<<i<<endl;
        return 0;
    }

#include <bits/stdc++.h>
using namespace std;
int n,k,x;
int main()
{
    //freopen("b1.inp","r",stdin);
    //freopen("b1.out","w",stdout);
    cin>>n>>k;
    x=((240-k)/5)*2;x=sqrt(x);
    cout<<min(x,n);
    return 0;
}

#include <iostream>
using namespace std;
int main()
{
	int n, k;
	cin>>n>>k;
	int *mas = new int[n];
	mas[0]=5;
	for (int i=1;i<n;i++)
	{
		mas[i]=mas[0]+(5*i)+mas[i-1];
	}
	int i;
	for (i=n;;)
	{
		if (mas[i-1]+k>240) i--;
		else break;

	}
	cout<<i<<endl;
	delete[] mas;
//	system("pause");
	return 0;
}

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

#define in_file(filename) 	freopen(filename, "r", stdin)
#define out_file(filename) freopen(filename, "w", stdout)
#define fast_io 				ios_base::sync_with_stdio(false); cin.tie(NULL)
#define For(i, a, b) 		for(int i = (a); i < (b); i++)
#define Fore(i, a, b)		for(int i = (a); i <= (b); i++)
#define ec 						"\n"
#define all(stl)				(stl).begin(), (stl).end()
#define fi 						first
#define se 						second

typedef long long ll;
const ll INF = 1LL<<60;
const double PI = 3.14159265358979;
const int MOD = 1000000007;

int res, cnt = 1, a[11];
int main()
{
	fast_io;
	// in_file("../input.txt");
	// out_file("../output.txt");
	int n, k, t;
	cin >> n >> k;
	t = 240 - k;
	while ((res+(5*cnt)) <= t) {
		res += (5*cnt);
		if ((res+(5*cnt)) <= t) cnt++;
		if (cnt == n) break;
	}
	cout << cnt;
}

#include <algorithm>
#include <string>
#include<iostream>
using namespace std;
#define ll long long

int main() {
	int n, k, total = 0, cn = 0;
	cin >> n >> k;
	for (int i = 1; i <= n; i++) {
		total += 5 * i;
	}
	//cout << "time to do all problems is: " << total << endl;
	int time = 240 - k;
	if (time >= total) {
		cout << n;
	}
	else {
		int j = 1;
		while (time >= 5) {
			time -= 5 * j;
			if (time > 0)
				cn++;
			j++;
		}
		cout << cn;
	}
	return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n,k;
	cin>>n>>k;
	int z;
	z=240-k;
	int j=1;
	int sum=0;
	while(z>=0)
	{
		z=z-(j*5);
		sum++;
		j++;
		break;
	}
	cout<<sum+1<<endl;
    return 0;
}

#include<iostream>
using namespace std;
int main()
{
	int n,k,total,i,z=1;
	cin>>n>>k;
	total=0;
	for(i=1;i<=n;i++)
	{
		total+=5*i;
		if(total+k>240)
		{
			z=0;}

	}if(z==0)
	cout<<i-2;
	else
	cout<<i-1;
}

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n,k,t,a=1,b=0,c=5;
    cin>>n>>k;
    t=240-k;
    for(int i=1; i<=n; i++)
    {
        if(c<=t)
        {
            b++;
            c=c+i*5;
        }

    }
    cout<<b;
    return 0;
}

#include<bits/stdc++.h>

using namespace std;
int n,k,cnt=0,t=5;
int main(){
	cin>>n>>k;
	k=240-k;
	while(k>=0){
		cnt++;
		k-=t;
		t+=5;
	}
	if(cnt>n)
		cout<<n;
	else
		cout<<cnt;

return 0;
}

    #include<bits/stdc++.h>
    using namespace std;
    int main(){
        int n,k;
        int trem = 240 - k;
        int a[n+1];
        int i;
        a[0]  = 0;
        for(i=1;i<=n;i++){
            a[i] = a[i-1]+5*i;
            }
            i=1;
        while(a[i]<trem){
            i++;
        }
        cout<<i<<endl;
        return 0;
    }

#include<stdio.h>

int main(){
	int n,k;
    scanf("%d %d",&n,&k);
    k = 240-k;
    int flag = 5;
    int s=0;
    int i=0;
    while(flag+=5){
    if(k-flag>=0) {
        k-=flag;
        s++;
    }
    else    break;
 if(flag/5==n) break;
}
printf("%d\n",s);
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,m;
    cin>>n>>m;
    int sum=0;
    int c=0;
    int r=240-m;
    for(int i=1;i<=n;i++)
    {
        sum+=5*i;
        if(sum>=r)
        c++;
    }
    cout<<c;
}

#include<bits/stdc++.h>

using namespace std;

int main() {
  int n, k, x = 0;
  cin >> n >> k;
  int y = 240 - k;
  while(y - (x+1)*5 >= 0) {
    y -= (x+1)*5;
    x++;
  }
  cout << x;
}

/* Bismillahir Rahmanir Rahim */
#include<stdio.h>
int main()
{
    int a,i,j,k,t,s,p;
    scanf("%d %d",&a,&k);
    t=240-k;
    for(i=1;i<=a;i++)
    {
        t=t-(5*i);
        if(t<5)
        {
            s=i;
            break;
        }
    }
    if(s>a)
        s=a;
    printf("%d\n",s);
    return 0;
}

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int main()
{
    long n,k;
    cin>>n>>k;
    int bal_t=240-k;
    int i=1;
    while(i<=n && bal_t>0)
    {
        bal_t=bal_t-(i*5);
        i++;
    }
    cout<<i<<endl;
    return 0;
}

#include<iostream>
using namespace std;
int n,a[10],k;
int fn(int t)
{
    if(a[t]>(240-k))
     return 1;
    else
     return 0;
}
int main()
{
    cin>>n>>k;
    int f=0,l,mid;
    a[0]=5;
    for(int i=1;i<n;i++)
     a[i]=((i+1)*5)+a[i-1];
    l=n-1;
    if(a[n-1]<=(mid-k))
     f=n-1;

    else
    while(f<l)
    {
        mid=(f+l)/2;
        if(fn(mid))
         l=mid-1;
        else
         f=mid+1;
    }
    cout<<f;
    return 0;
}

#include <iostream>

using namespace std;

int x ,y ,n , k ;

int main()
{
    cin >> n >> k ;
    x=240-k ;

    for(int i=1 ;i<=n; i++)
    {
        x=x-(i*5) ;
        if(x>0 )
        {
            if(i==n)
            {
                cout << n ;
                break ;
            }
            if((x-5-(5*i)<0))
            {
                cout << i ;
                break ;
            }else if((x-5-(5*i)==0))
            {
                cout << i+1 ;
            }
        }else if(x<0)
        {
            cout << i-1 ;
            break ;
        }

    }

  return 0 ;
}

// Example program
#include <iostream>
#include <string>
using namespace std;
int main()
{
    int n, t;
    cin >> n >> t;
    int k = 240 - t;
    int sum = 0, i = 1;
    if(n == 1 && k >= 5)
    {
        cout << 1;
        return 0;
    }
    while(sum + i * 5 <= k && i <= n)
    {
        sum += i * 5;
        i++;
        if(i == n && sum + i * 5 <= k)
        {
            cout << i;
            return 0;
        }
        if(sum + i * 5 > k)
        {
            cout << i - 1;
            return 0;
        }
    }
    cout << i;
    return 0;
}

#include <iostream>
using namespace std;
int n,k;
int main(){
	cin>>n>>k;
	int t=240,i=5,j=0;
	t-=k;
	while(k>0){
		t-=i;
		i*=2;
		j++;
		if(t<0)
			j--;
		if(j>=n)
			break;
	}
	cout<<j<<endl;
//	system("pause");
	return 0;
}

#include"stdio.h"

int main()
{
	int n, k;
	scanf("%d", &n);
	scanf("%d", &k);
	int timedu = 239 - k;
	int dembai = 0;
	int i = 1;
	while (timedu > 0 && dembai < n)
	{
		timedu -= i * 5;
		dembai++;
		i++;
		if (timedu < i * 5)
			break;
	}
	printf("%d", dembai);
}

#include <bits/stdc++.h>

using namespace std;
int n,k,dd;
int main()
{
    //freopen("tst.inp","r",stdin);
    cin >> n >> k;
    for (int i=1;i<=7;i++)
         if (5*i*(i+1)/2+k<=240) dd=i;
    cout << dd;
}

#include<cstdio>
#include<cstring>
int main()
{
	int n,k,ans=0;
	scanf("%d %d",&k,&n);
	n=240-n;
	for(int i=1;i<=k;++i)
	{
		n-=i*5;
		if(n<=0)	break;
		++ans;
	}
	printf("%d",ans);
	return 0;
}

#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=(a); i<(b); i++)
#define all(c) (c).begin(),(c).end()
#define rall(c) (c).rbegin(),(c).rend()
#define sort(v,n) sort(v,v+n);
#define vsort(v) sort(v.begin(),v.end());
#define vvsort(v) sort(v.begin(),v.end(),greater<int>());
#define ll long long
#define pb(a) push_back(a)
#define fi first
#define se second
#define inf 999999999
using namespace std;
typedef pair<int,int> p;
typedef pair<ll,ll> lp;
typedef priority_queue<int> pq;
typedef priority_queue<int,vector<int>,greater<int> > rpq;
bool is_uruu(int y) {
        return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);
}
const ll MOD=1e9+7;
const double PI=acos(-1.0);
//----------------------------------------------------------------------------------------------------------------------------------//

int main(){
        int n,m;
        cin>>n>>m;
        int k=240-m;
        int count=0;
        while(count<=n) {
                if(count*5<=k) {
                        count++;
                        k-=count*5;
                }else{
                        break;
                }
        }
        cout<<count<<endl;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
     int n=0,k=0,m=0;
     cin>>n>>k;
     int i;
     for(i=1;i<n;i++)
     {
          m+=5*i;
          if(m+k==240)
          {     cout<<i<<"\n";
               break;
          }
     }
     return 0;
}

#include <iostream>

using namespace std;

int main(){

	int n, k, cm, w;

	int vet[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

	cin >> n >> k;

	if(n < 1 or n > 10 and k < 1 or k > 240){

		return 0;

	}

	if(n == 10){

		cout << 0 << endl;

		return 0;

	}

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

		vet[i] = 5 * vet[i] + vet[i - 1];

		cm = vet[i];

	}

	if(240 - k < cm){

		cout << n - 1 << endl;

	}else{

		cout << n << endl;

	}

	return 0;

}

#include <iostream>
#include <cmath>

using namespace std;

int main(){
    int n,k;
    cin>>n>>k;
    int time=240-k;
    if(floor(sqrt(time*2.0/5)<n)) cout<<floor(sqrt(time*2.0/5));
    else cout<<n;
    return 0;
}

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

using namespace std;

int main()
{
    int n,k;
    cin>>n>>k;
    k=240-k;
    if(k>=0 && k<=4)
    cout<<0;
    else if(k>=5)
    {
        for(int i=1;i<=n;i++)
        {
            k=k-5*i;
            if(k>=(5*i+1) && i!=n)
            continue;
            else
            {
            cout<<i;
            break;
        }
        }
    }

}

#include <iostream>

using namespace std;
int main()
{
int i,j,k;
cin>> i >> j;
int t=240-j;
if (t<5){
    cout << 0;
    return 0;
}
for (k=1; k<i;k++){
    t= t - (5*k);
    if (t<5){

        break;
    }

}
 cout << k;

return 0;
}

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

using namespace std;

unsigned int availCntMin = 240;
unsigned int n;
unsigned int k;

int getTime(int i) {
    unsigned int ans = 0;
    for (int j = 1; j <= i; ++j) {
        ans += (5 * j);
    }
    return ans;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> k;
    availCntMin -= k;
    unsigned int l = 1, r = n, m;
    while ((r - l) / 2 > 0 ) {
        m = l + (r - l) / 2;
        if (getTime(m) > availCntMin) {
            r = m;
        }
        else if (getTime(m) < availCntMin){
            l = m;
        }
        else {
            break;
        }
    }
    if (getTime(m + 1) <= availCntMin) {
        ++m;
    }
    else if (getTime(m + 2) <= availCntMin) {
        m += 2;
    }
    else if (availCntMin == 0) {
        m = 0;
    }
    cout << m;
}

#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
	int n;
	int time;
	cin>>n>>time;
	int valuetime=4*60-time;
	int i=1;
	int cs=0;
	while(valuetime-i*5>=0)
	{
		valuetime-=i*5;
		if(n==i)
		{
			break;
		}
		cs++;
		i++;
	}
	cout<<cs<<endl;
	getchar();
	getchar();
	getchar();
	return 0;
}

#include<stdio.h>
int main()
{
	int n,k,yushu,i;
	scanf("%d %d",&n,&k);
	yushu=240-k;
	i=1;
	while (i<=n&&yushu/(i*5)>0){
		yushu=yushu-i*5;
		i=i+1;
		printf ("%d %d\n",i,yushu);
	}
	printf ("%d\n",i-1);
	return 0;
}

#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
	int n;
	int time;
	cin>>n>>time;
	int valuetime=4*60-time;
	int i=1;
	int cs=0;
	while(valuetime-i*5>0&&n>=i)
	{
		valuetime-=i*5;
		cs++;
		i++;
	}
	cout<<cs<<endl;
	getchar();
	getchar();
	getchar();
	return 0;
}

#include <iostream>
using namespace std;
main () {
	int n, k, a = 1200, i = 0, b = 0;
	cin>>n>>k;
	a+=k;

	do 	{
	 		b = a + (5*i);
	 		i++;
		} while (i <= n && b <= 1440);
		cout<<(i-1)<<endl;
}

#include <bits/stdc++.h>

using namespace std;

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

	int min_left=240-k;
	int i=0,result=0;
	while(min_left>0)
	{
	    i+=5;
	    min_left-=i;
	    result++;
	    if(result==n)
	    {
	        cout<<n;
	        return 0;
	    }
	}
	cout<<result-1;
	return 0;
}

#include <iostream>
using namespace std;
int main()
{
    int n,t;
    cin>>n>>t;
    int time=240-t;
    int sum=0;
    for(int i=0;i<n;i++)
        sum+=5*i;
    if(sum<time)
        cout<<n<<endl;
    else{
         for(int i=1;i<=n;i++){
             sum+=5*i;
            if(sum<time)
               continue;
            else if(sum==time)
               cout<<i<<endl;
            else
           {
               cout<<i-1<<endl;
               break;
           }
    }
    }
    return 0;
}

//http://codeforces.com/problemset/problem/750/A

#include<bits/stdc++.h>

using namespace std;

int main()
{
	int n,k;
	cin>>n>>k;
	k=240-k;
	k/=5;
	int sum=0,c=1;
	while(sum<k && c<=n)
	{
		sum+=c++;
		cout<<k<<" "<<sum<<" "<<c<<endl;
	}
	if(sum==k || c-1==n)
		c++;
	cout<<c-2<<endl;
	return 0;
}

#include <bits/stdc++.h>

#define LOCAL
#define ll long long
#define lll unsigned long long
#define MAX 1000009
#define mod 1000000007

using namespace std;

int n,m;
int main()
{
    while(~scanf("%d %d",&n,&m)){
       int time = 240 - m;
       if(time<5){
           cout<<0<<endl;
       }else{
        int sum = 0;
        int ans = -1;
        int time = 240 - m;
        for(int i = 1;i<=n;i++){
            sum = sum + i*5;
            if(sum>time){
                ans = i - 1;
                break;
            }
            else if(sum == time){
                ans = i;
                break;
            }
        }
        if(ans == 0){
            ans = n;
        }
        cout<<ans<<endl;
       }
    }
}

// A. New Year and Hurry - CodeForces
#include<bits/stdc++.h>
using namespace std;

void In_Out() {
#ifndef ONLINE_JUDGE
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
}

int get_solve_time(int &number) {
	if (number == 1) {
		return 5;
	} else return ((number / 2) * (10 + (number - 1) * 5));
}

int max_questions(int num, const int &k) {
	int left_time = 240 - k;
	int solve_time = get_solve_time(num);
	// cout << "num: " << num << " solve_time: " << solve_time << endl;
	if (solve_time <= left_time && left_time != 0) {
		return num;
	} else if (solve_time == 0 && left_time == 0) {
		return num - 1;
	} else {
		max_questions(num - 1, k);
	}
}

int main() {
	In_Out();
	int n, k;
	cin >> n >> k;
	cout << max_questions(n, k);
}
// Input
// The only line of the input contains two integers n and k (1 ≤ n ≤ 10, 1 ≤ k ≤ 240) — the number of the problems in the contest and the number of minutes Limak needs to get to the party from his house.
// Output
// Print one integer, denoting the maximum possible number of problems Limak can solve so that he could get to the party at midnight or earlier.

#include <iostream>
using namespace std;
int main () {
	int n, k, time, i = 1, final = 0;
	cin >> n >> k;
	time = 240 - k;
	while (time > 0) {
		k = 5 * i;
		time -= k;
		i++;
		if (n == i) {
			i += 2;
			break;
		}
	}
	cout << i - 2 << endl;
	return 0;
}

#include <iostream>
using namespace std;

int main()
{
    int n, k, ans = 0;
    cin >> n >> k;
    while(ans <= n && ans * 5 * k <= 240){
        k += (ans * 5);
        ++ans;
    }
    cout << ans - 1 << endl;
    return 0;
}

#include<bits/stdc++.h>

using namespace std;

int main()
{
    int n, k;
    cin>>n>>k;
    int res = 0, time = 5, i=1;
    while((240-time)>=k)
    {
        res++;
        i++;
        time+=(5*i);
    }
    cout<<res;
}

#include <iostream>
using namespace std;

int findHowManyQuestions(int n, int mid)
{
	int time = 0;
	int ans = 0;
	for(int i=1; i<=n; ++i)
	{
		time += (i*5);
		if(time <= mid)
		{
			ans += 1;
		}
	}
	return ans;
}

void solve()
{
	int n,k; cin >> n >> k;
	int e = 240 - k;
	int s = 0;
	int ans = 0;
	while(s<=e)
	{
		int mid = (s+e)/2;
		cout << "mid is " << mid << endl;
		ans = findHowManyQuestions(n,mid);
		s = mid+1;
	}
	cout << ans << endl;
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	solve();
	return 0;
}

#include <iostream>

using namespace std;

int main()
{
    int n,k,sum=0,co=0,sum1=0;
    cin>>n>>k;
    sum1=240-k;
    if(k==240)
        cout<<0<<endl;
    else
    {
        for(int i=1; i<=n; i++)
        {
            sum+=5*i;
            co++;
            if(sum1<sum+5*(i+1)) break;
        }
    cout<<co<<endl;
    }
    return 0;
}

#include <iostream>
#include <cmath>

using namespace std;

int main(){
    int n,k;
    cin>>n>>k;
    int time=240-k;
    int i=1,sum=0;
    while(sum<=time){
        sum+=5*i;
        i++;
    }
    if(i<n) cout<<i-2;
    else cout<<n;
    return 0;
}

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

int z , p , q , w ;

deque<int>vc,cv;

string a = "aeiouy";

int main( ) {

    int n , m ;
    cin >> n >> m ;
    if(m>=238){
        cout<<0<<endl;
        return 0 ;
    }
    int b[10000];
    int k = ( 240 - m ) / 5 ;
    for(int i = 1 ; i < 10000 ; i ++ ){
        b[i]=(i*(i+1))/2;
    }
    for(int i = 0 ; i < 10000 ; i ++ ){
        if(k<=b[i]){
            cout<<min((i+1),n)<<endl;
            return 0 ;
        }
        k -= b[i];
    }

}

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

int main() {
	int n,k;
	cin>>n>>k;
	int q=240-k;
	vector<int>a(n);
	a[0]=5;
	for(int i=1;i<n;++i){
		a[i]=(i+1)*5+a[i-1];
	}
	bool flag=false;
	int key=q;
	int l=0;
	int r=n-1;
	int m;
	while((l<=r)&&(flag!=true)){
		m=round((l+r)/2.);
		if(a[m]==key)flag=true;
		if(a[m]>key)r=m-1;
		else l=m+1;
	}
	if(flag)cout<<m+1;
	else if(n>5)cout<<m+1;
	else cout<<m;
	return 0;
}

#include<iostream>
using namespace std;
int main()
{
    int prob, party,left,left_now,i;
    cin>>prob;
    if (prob==10)
    prob--;
    cin>>party;
    left = 240-party;
    if (left>5){

        for(i=1;i<prob;i++)
    {
        left = left-(5*i);

        if(left<5*(i+1))
        {
            cout<<i;
            return 0;
        }

    }

        cout<<i;
    }
    else
    cout<<0;

    return 0;
}

#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <cstring>
int n,k;

int main()
{
    scanf("%d %d",&n,&k);
    int last = 240 - k;
    int res = 0;
    for(int i = 1; i <= n; i++)
    {
        if( i*5 < last)
        {
            last -= i*5;
            res++;
        }
        else
            break;
    }
    printf("%d\n",res);
    return 0;
}

#include<iostream>
#include<bits/stdc++.h>
using namespace std;
int bs(int n,int k){
    k=240-k;
    int l=1,h=n,c;
    while(l<=h){
        int m=(l+h)/2;
        int t=(5*(m)*(m+1))/2;
        if(t==k){
            c=m;
            return c;
        }
        if(t<k){
            c=m;
            l=m+1;
        }
        else{
            h=m-1;
        }
    }
    return c;
}
int main(){
    int n, k;
    cin>>n>>k;
    cout<<bs(n,k);
    return 0;
}

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

int main()
{
// #ifndef ONLINE_JUDGE
// 	freopen("in.txt","r",stdin);
// 	freopen("out.txt","w",stdout);
// #endif
	int n , time ; cin >> n >> time ;
	int time_left = 240 - time ;
	int count = 1 ;
	int sum = 0 ;
	for(int i = 1 ; i <= n ; i++)
	{
		int prob = 5*i ;
		sum += prob ;
		cout << sum << " " << prob << " " << time_left << endl;
		if(sum <= time_left)
		{
			count ++;
			time_left -= prob ;
		}
		else break;
	}
	if(sum>5)cout << count ;
    else cout << 0 ;
	return 0 ;
}

#include<iostream>
using namespace std;
int main(){
    int n,k,i;
    cin>>n>>k;
    n=n-k;
    for(i=1;;i++){
        n-=5*i;
        if(n<0) break;
    }
    cout<<i-1;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n,k,rem,i,ans=0;
    cin>>n>>k;

    rem=240-k;
    for( i=1; i<=n && rem>=0 ; i++)
    {
        rem=rem-(5*i);
        ans++;

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

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

int n, r;
int main()
{
    cin >> n >> r;
    r = 240 - r;
    int i = 1;
    int dem = 0;
    while(dem <= r){
        dem += 5*i;
        if(dem > r)
            break;
        i++;
    }
    cout << i - 1;
}

#pragma comment(linker, "/STACK:10000000000")
#pragma GCC optimize("O3")
#define _CRT_SECURE_NO_WARNINGS
#include <stdlib.h>
#include <stdio.h>
#include <iostream>
#include <sstream>
#include <iomanip>
#include <math.h>
#include <map>
#include <chrono>
#include <set>
#include <stack>
#include <vector>
#include <time.h>
#include <random>
#include <algorithm>
#include <string>
#include <string.h>
#include <queue>
#include <deque>
#include <functional>
#include <cctype>
#include <list>
#include <unordered_set>
#include <unordered_map>
#include <bitset>
#include <complex>
#define rt return
#define mp make_pair
#define endl '\n'
#define sqr(x) ((x) * (x))
#define all(x) (x).begin(), (x).end()
#define rep(x) for (int rep_iter = 0; rep_iter < x; ++rep_iter)
#define fnd(x, y) (x.find(y) != x.end())
#define fndv(x, y) (find(all(x), y) != end(x))
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
typedef long double ldb;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<db, db> pdd;
typedef unsigned char bt;
typedef unsigned int uint;
const int MOD = 1000000007;
const int INF = 1000000007LL;
const ll INF2 = 1LL << 62LL;
const long double EPS = 1e-9;
#ifdef _DEBUG
const int SIZE = 120;
#endif
#ifndef _DEBUG
const int SIZE = 500010; //200010
#endif
mt19937 rng(time(0));
uniform_int_distribution<int> uid(-1000000000, 1000000000);

int main() {
#ifndef ONLINE_JUDGE
	freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout);
#endif
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	int n, k, ans = 0;
	cin >> n >> k;
	k = 240 - k;
	for (int i = 1; i * 5 <= k; ++i) {
		ans = i;
		k -= i * 5;
	}
	cout << ans;

	return 0;
}

#include <bits/stdc++.h>
using namespace std;
int main() {

	int n, k;
	cin >> n >> k;
	if (k == 240) {
		cout << 0;
		return 0;
	}
	int cnt = 0, ans = 0;
	for (int i = 1; i <= n; i++) {
		if (cnt + (i * 5) > (240 - k)) {
			ans = i - 1;
			break;
		}
		cnt += (i * 5);
	}
	if (!ans) {
		cout << n;
	}
	else {
		cout << ans;
	}
	return 0;
}

#include <iostream>
using namespace std;
int main ()
{
    int n,k,ile_spr(0);
    cin >> n >> k;
    for(int i=0; i<n; i++){
        int d;
        d+=5;
        ile_spr+=d;
    }
        while(ile_spr+k>=240){
            ile_spr-=5;
            n--;
    cout << n;
            return 0;
        }

}

#include<bits/stdc++.h>
using namespace std;
int main(){
int n,k,i=1;
cin>>n>>k;
int sum=0;
int p=240-k;
while(p>sum && i!=n){
sum=sum+5*i;
i++;
}cout<<i-2<<endl;
return 0;
}