View Code of Problem 30

#include <stdio.h>
int main()
{
  int i,n;
  while (scanf("%d",&n)!=EOF)
  {
    int sum=0;
    for (i=1;i<=n;i++)
    {
      sum=sum+i;
    }
    printf("%d\n",sum);
  }
  return 0;
}