Working with Pointers

Another way we can work with references instead of values is through pointers. A pointer is a special type of variable that contains the address of another variable in memory. For working with pointers, we use two important operators:

• & - gets the address of a variable
• * - gets the value at an address (dereference)

Let's look at an example:

int number = 42;           // Regular variable
int* pointer = &number;    // Pointer to variable number

*pointer = 10;            // Change value through pointer
std::cout << number;      // Prints: 10

Notice that:

• The pointer type must match the variable type (int* for int)
• The * symbol is part of the type in declaration (int*)
• The * operator before a pointer accesses the value

A pointer can also be empty (point nowhere) using the value nullptr:

int* pointer = nullptr;  // Empty pointer

if (pointer != nullptr) {
    std::cout << *pointer;  // Safe usage
}

It's important to always check if a pointer isn't nullptr before using it, otherwise the program might crash!