这题只能用C++写,害得我复习了一下C++语法@烤点老白薯
#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) { long long x = 1; for (int i=1;i<=n;i++){ x *= i; } return x; }