[HDOJ]1001 Sum Problem

Sum Problem

Time Limit: 1000/500 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)

Total Submission(s): 546669    Accepted Submission(s): 138766

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

#include<stdio.h>

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