题解 | #函数实现计算一个数的阶乘#

#include <iostream>
using namespace std;

long long factorial(int n);

int main() {

    int n;
    cin >> n;

    cout << factorial(n) << endl;

    return 0;
}

long long factorial(int n) {

    // write your code here......
    long long ans=1;
    for(int i=2;i<=n;i++){
        ans*=i;
    }
    return ans;
}