Right Rotate an Array in Java - The Coding Shala

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 In this post, we will learn how to right rotate the elements of an array using the Java program.

Right Rotate an Array in Java

Write a Java program to Right Rotate the elements of an array by 1 position.

Example: 

Input: [1, 2, 3, 4, 5]
Output: [5, 1, 2, 3, 4]

Solution 1

We need to rotate the elements to the right by 1 position. We can store the last element in one variable and using for loop will shift all the elements to the right by 1 position.

syntax: arr[i] = arr[i-1]

After shifting all the elements move the last element[stored in variable] to the first index.

Java Program: 

/**
 * https://www.thecodingshala.com/
 */

import java.util.*;

public class Main {

    public static int[] rightRotate(int[] arr) {
        // last element will become first
        int last = arr[arr.length-1];
        for (int i = arr.length-1; i > 0; i--) {
            // shift the elements to right
            arr[i] = arr[i-1];
        }
        arr[0] = last;
        return arr;
    }

    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 4, 5};
        System.out.println("Array before rotation: ");
        for (int i = 0; i < arr.length; i++) {
            System.out.print(arr[i] + " ");
        }

        System.out.println("\nArray after right rotation by 1: ");
        arr = rightRotate(arr);
        for (int i = 0; i < arr.length; i++) {
            System.out.print(arr[i] + " ");
        }
    }
}

Output: 

Array before rotation: 
1 2 3 4 5 
Array after right rotation by 1: 
5 1 2 3 4


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