Comments

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  -1

  

  rokudomukuro  commented on Feb. 15, 2019, 3:31 a.m.

  _<

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  0

  

  tungcntt2k58  commented on Jan. 25, 2019, 8:49 a.m. ← edited →

  include<math.h>

  #include<iostream>
  using namespace std;
  int main()
  {
      int t=1;
      int n;
      cin>>n;
      for(int i=2;i<=n;i++)
      {
          t+=i;
      }
      cin>>t;
  }