Example: In-Place Array Reversal with Two Pointers in Java

// In-Place Array Reversal with Two Pointers
import java.util.Arrays; // For printing the array easily

public class Main {
    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 4, 5};
        System.out.println("Original Array: " + Arrays.toString(arr));

        // Step 1: Initialize two pointers
        int start = 0;
        int end = arr.length - 1;

        // Step 2: Loop while the start pointer is less than the end pointer
        while (start < end) {
            // Step 3: Swap elements at start and end positions
            int temp = arr[start]; // Store the element at 'start'
            arr[start] = arr[end]; // Replace 'start' element with 'end' element
            arr[end] = temp;       // Replace 'end' element with stored 'start' element

            // Step 4: Move pointers towards the center
            start++;
            end--;
        }

        System.out.println("Reversed Array (Two Pointers): " + Arrays.toString(arr));
    }
}