View Code of Problem 30

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