2018/12/28 hdu1001 水题

hdu1001
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

#include<iostream>
using namespace std;
int main()
{
    int n, sum=0;
    while (cin >> n)
    {
        for (int i = 1; i <= n; i++)
        {
            sum = sum + i;
        }
        cout << sum << endl << endl;
        sum = 0;
    }
}

大意：累加1+2+…+n,并输出一行空行;
注意点：有点坑要输出一空行，所以两次endl；
sum计算完要记得初始化，或者选择把sum定义放在里面。
e.g.

while()
{
	int sum=0;
}