1. Introduction

Rotating an array means moving its elements to the right or to the left by a certain number of positions. In this blog post, we will see how to rotate an array to the right by a given number of positions in Java.

2. Program Steps

1. Initialize the array and the number of positions n by which the array has to be rotated.

2. Compute the length of the array.

3. Create a temporary array of size n to store the elements that will be shifted.

4. Copy the last n elements from the original array to the temporary array.

5. Shift the remaining elements in the original array to the right by n positions.

6. Copy the elements from the temporary array back to the original array at the beginning.

3. Code Program

public class RotateArray {

    public static void main(String[] args) {
        // Step 1: Initialize the array and the number of positions n by which the array has to be rotated
        int[] array = {1, 2, 3, 4, 5, 6, 7};
        int n = 3;

        // Step 2: Compute the length of the array
        int length = array.length;

        // Step 3: Create a temporary array of size n to store the elements that will be shifted
        int[] temp = new int[n];

        // Step 4: Copy the last n elements from the original array to the temporary array
        System.arraycopy(array, length - n, temp, 0, n);

        // Step 5: Shift the remaining elements in the original array to the right by n positions
        System.arraycopy(array, 0, array, n, length - n);

        // Step 6: Copy the elements from the temporary array back to the original array at the beginning
        System.arraycopy(temp, 0, array, 0, n);

        // Printing the rotated array
        for (int i : array) {
            System.out.print(i + " ");
        }
    }
}

Output:

5 6 7 1 2 3 4

4. Step By Step Explanation

In Step 1, we initialize the array and the number of positions n by which the array has to be rotated.

During Step 2, we compute the length of the array for later use in copying and shifting elements.

In Step 3, a temporary array of size n is created to store the elements that will be shifted.

For Step 4, we copy the last n elements from the original array to the temporary array using System.arraycopy().

In Step 5, we shift the remaining elements in the original array to the right by n positions.

Finally, in Step 6, we copy the elements from the temporary array back to the original array at the beginning, completing the rotation. After the rotation, we print out the modified array.