Sum Problem

Sum Problem

Time Limit: 500ms Memory limit: 32768K 有疑问？点这里^_^

题目描述

Hey, welcome to HDOJ(Hangzhou Dianzi University Online Judge).

In this problem, your task is to calculate SUM(n) = 1 + 2 + 3 + ... + n.

输入

The input will consist of a series of integers n, one integer per line.

输出

For each case, output SUM(n) in one line, followed by a blank line. You may assume the result will be in the range of 32-bit signed integer.

示例输入

1
100

示例输出

1

5050

来源

sdut

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