Select Driver Overload

#include <iostream>
using namespace std;

void init(int pin) {
    cout << "PIN " << pin;
}

void init(int* portPtr) {
    cout << "PORT NULL";
}

int main() {
    int mode;
    cin >> mode;

    if (mode == 1) {
        int pin;
        cin >> pin;
        init(pin);        // calls int overload
    }
    else if (mode == 2) {
        init(nullptr);    // calls pointer overload
    }

    return 0;
}

Solving Approach