FKY 2023-08-29 20:25:12 3 返回题目
#include<bits/stdc++.h> using namespace std; int main(){ int n, sum = 0; cin >> n; for (int i = 1; i <= n; i++){ if (i % 2 == 0){ sum = sum + i; } } cout << sum; return 0; }
