Swap Two Numbers Using Pointers in C

Summary: This program swaps the values of two integers using a function that accepts pointers. The swap is performed through memory manipulation using the address-of and dereference operators.

#include <stdio.h>

// Function to swap two integers using pointers
void swap(int *a, int *b) {
    int temp = *a;
    *a = *b;
    *b = temp;
}

int main() {
    int x, y;

    // Input two integers
    printf("Enter two numbers: ");
    scanf("%d %d", &x, &y);

    // Before swapping
    printf("Before swap: a = %d, b = %d\n", x, y);

    // Swap values using pointer
    swap(&x, &y);

    // After swapping
    printf("After swap: a = %d, b = %d\n", x, y);

    return 0;
}

Explanation:

Pointer Arguments:
The function swap() uses int *a and int *b to access the memory addresses of the original variables.

Dereferencing:
*a and *b are used to get the values stored at the addresses. These are then swapped using a temporary variable.

Address-of Operator:
The & operator is used in main() to pass the addresses of variables x and y to the function.

Result:
Values of x and y are successfully swapped by the function since it modifies the memory directly.