title: summation of vector containing long long int using accumulation
body: <pre><code>#include &lt;iostream&gt;
  #include &lt;vector&gt;
  #include &lt;numeric&gt;
  #include &lt;iterator&gt;
  
  using namespace std;
  
  int main()
  {
      int N;
      cin&gt;&gt;N;
      long long int x,sum=0;
      std::vector&lt;long long int&gt; v;
      for(int i=0;i&lt;N;i++)
      {
          cin&gt;&gt;x;
          v.push_back(x);
      }
      /*vector&lt;long long int&gt;::iterator itr;
      itr = v.begin();
      for(itr=v.begin();itr&lt;v.end();itr++)
          sum += *itr;*/
      sum = accumulate(v.begin(),v.end(),0);
      cout&lt;&lt;sum;
      return 0;
  }
  </code></pre>
  
  <p>My program is returning abstract value using accumulate, but if I use the for loop, the answer is coming.</p>