Pointer Reference Increment

#include <iostream>

// Define incrementPtr(int* x)
void incrementPtr(int* x) {
    // Increment the value pointed to by x
    // Do nothing if x is nullptr
    if(x != NULL) {
        (*x)++;
    }
}

// Define incrementRef(int& x)
void incrementRef(int& x) {
    // Increment the referenced value
    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;
}