View Code of Problem 30

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