题目描述

求区间的和

C++ 代码

#include <bits/stdc++.h>

using namespace std;
int sum(int l, int r)
{
    int res = 0;
     cin>> l >> r;
    for(int i = l; i <= r; i++){
       res += i;   
    }
    return res;
}
int main()
{
    int l, r, res = 0;
    cin>> l >> r;
    cout<< sum(l, r) << endl;
    return 0;
}