Pointer Reference Increment

#include <iostream>

void incrementPtr(int* x){
    if(!x) {return;}
    (*x)++;
}

void incrementRef(int& x){
    x++;
}

int main() {
    int n;
    std::cin >> n;

    int a = n;
    incrementPtr(&a);
    std::cout << "After incrementPtr: " << a << "\n";

    int b = n;
    incrementRef(b);
    std::cout << "After incrementRef: " << b;

    return 0;
}

Solving Approach