Pointer Reference Increment

#include <iostream>

// Define incrementPtr(int* x)
// Increment the value pointed to by x
// Do nothing if x is nullptr

void incrementPtr (int* x){

    //if(x == nullptr) return;

    (*x)++;

}

// Define incrementRef(int& x)
// Increment the referenced value


void incrementRef(int& x){

   //if(x == std::nullptr) return;

    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