Sum Problem

Sum Problem

Time Limit: 1000/500 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 201094    Accepted Submission(s): 48459

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

 

 

程序代码：

 

 

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