#include <iostream>

using namespace std;

void Countdown(size_t i);

int main() {

    size_t i;

    for(i=0; i < 10; i ++) {
        cout << "Counting down from " << i << endl;
        Countdown(i);
        cout << endl;
    }

    return 0;
}

void Countdown(size_t i){
    cout << i << endl;
    if (i > 0) {
       Countdown(i-1);
    }

    return;
}