Rotation of an array using O(1) Space Complexity Java

PROGRAM TO ROTATE AN ARRAY USING REVERSAL ALGORITHM

import java.util.Scanner;

public class Main {

  static void reverse(int arr[], int start, int end) {

    while(start<end) {

      int temp = arr[start];

      arr[start] = arr[end];

      arr[end] = temp;

      start++;

      end--;

    }

  }

  public static void main(String[] args) {

    Scanner sc = new Scanner(System.in);

    // n = number of array elements

    int n = sc.nextInt();

    // k = number of positions by which array should be rotated

    int k = sc.nextInt();

    int[] arr = new int[n];

    for(int j=0; j<n; j++)

      arr[j] = sc.nextInt();

      

    k %= n;

    reverse(arr, 0, arr.length-1);

    reverse(arr, 0, k-1);

    reverse(arr, k, arr.length-1);

    for(int  j=0; j<n; j++)

      System.out.print(arr[j] + " ");

  }

}

OUTPUT

5 1

1 2 3 4 5

5 1 2 3 4