sum problem C语言试题

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

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

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

Output
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.

Sample Input
1
100

Sample Output
1

5050

Author
DOOM III

我刚学，有谁知道怎么做？用C语言。。。。

题就这么多啊？貌似没有规定多个n输入完成之后怎么判断算是结束输入，开始输出啊。
由于不知道你的判断输入结束的标志，我简化了这方面的操作，定义了能输入的数的数量：
#include<stdio.h>
#define count 5
int Sum(int n);
void main()
{
char c;
int Nums[count],i;
printf("Input a series of integers n, one integer per line:\n");
for(i = 0;i<count-1;i++)
{
scanf("%d",&Nums[i]);
}
Nums[i] = '\0';
printf("For each case, output SUM(n) in one line, followed by a blank line:\n");
for(i = 0;Nums[i]!='\0';i++)
{
printf("%d\n\n",Sum(Nums[i]));
}
printf("Author\nDoom III\n");
}
int Sum(int n)
{
int i,sum = 0;
for(i = 1;i<=n;i++)
{
sum+=i;
}
return sum;
}

//还是给你翻译成C语言代码吧
#include<iostream>
using std::cin;
using std::cout;
using std::endl;//直接换成#include<stdio.h>