View Code of Problem 30

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