View Code of Problem 30

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