各位数字积 cpp

#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;
}