起因
看到下面这样一段代码:
#include <stdio.h>
int main()
{
int n, sum = 0;
while (scanf("%d", &n) != -1) {
for (int i = 0; i <= n; i++) {
sum = sum + i;
}
printf("%d\n\n", sum);
sum = 0;
}
return 0;
}
代码的来源是什么HDOJ 1001问题的解答。在网上搜索了一下,是一个程序题,题目如下:
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.
NOTE:You may assume the result will be in the range of 32-bit signed integer.
Sample Input
1
100
Sample Output
1
5050
看了一圈网上贴出来的解答代码,基本上都用while循环,