Recursion और Call Stack

#include <stdio.h>

unsigned long long factorial(unsigned number) {
    return number < 2 ? 1 : number * factorial(number - 1);
}

int main(void) {
    printf("%llu\n", factorial(6));
}

#include <iostream>

constexpr unsigned long long factorial(unsigned number) {
    return number < 2 ? 1 : number * factorial(number - 1);
}

int main() {
    constexpr auto value = factorial(6);
    std::cout << value << '\n';
}