View Code of Problem 30

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