The Deep Connection

In C, pointers and arrays are nearly the same thing. In fact, the name of an array is actually a constant pointer that points to its very first element.

int arr[5] = {10, 20, 30, 40, 50};
// 'arr' is exactly the same as '&arr[0]'

Pointer Arithmetic

You can perform mathematical operations on pointers! However, they don't work like normal math:

• ptr + 1 doesn't add 1 byte; it moves the pointer to the next item of that type.
• If ptr is an int* (4 bytes), ptr + 1 jumps forward 4 bytes.
• If ptr is a char* (1 byte), ptr + 1 jumps forward 1 byte.

Two Ways to Access Arrays

Because of this connection, these two lines are identical to the C compiler:

1. arr[i]
2. *(arr + i)

Array of Pointers

You can have an array where every item is itself a pointer. This is extremely common for handling strings of different lengths.

char *names[] = {"Rahul", "Siksha", "Sarovar"};

Pointer to Pointer (Double Pointer)

A variable that stores the address of another pointer. This is used when you need a function to change where a pointer in another function is pointing.

int x = 5;
int *p = &x;
int **pp = &p; // pp points to p, which points to x

Function Pointers (Advanced)

A pointer can even point to the starting address of a Function! This allows you to pass logic as a parameter to another function (often called "Callbacks").

void (*fptr)(int) = &myFunction;
fptr(10); // Calls the function

Pointer arithmetic is one of the reasons C is so fast. Navigating an array with pointers is often more efficient for the CPU than using indices, although modern compilers are very good at optimizing both.