#include <iostream> #include <cmath> using namespace std; int p(int n) { int r = 1; while (n > 0) { r *= n % 10; n /= 10; } return r; } int main() { int r; cout << "输入一个数字"; cout << endl; cin >> r; cout << endl; r = p(r); cout << r; cout << endl; return 0; }