HDU 1001 Sum Problem

Sum Problem

Time Limit: 1000/500 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 170123    Accepted Submission(s): 40500

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

1100

 

Sample Output

15050

 

Author

DOOM III

 

分析：就是一个个叠加

代码：

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