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* num){
    if(num !=nullptr){
        *num = *num + 1;
        } 
    
}

// Define incrementRef(int& x)
// Increment the referenced value
void incrementRef(int &num){
    num = num + 1;
    
} 

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