题解 | 牛牛学数列4
牛牛学数列4
https://www.nowcoder.com/practice/586b114f52034688879342ba45779081
#include<bits/stdc++.h>
using namespace std;
int main(){
int n,sum=0,a=0;
cin >> n;
for (int i = 1;i<=n;i++){
sum += i;
a += sum;
}
cout <<a;
return 0;
}
一定要赋初始值