Print array after it is right rotated K times | Set 2

Given an array arr[] of size N and a value K, the task is to print the array rotated by K times to the right.

Examples:

Input: arr = {1, 3, 5, 7, 9}, K = 2
Output: 7 9 1 3 5

Input: arr = {1, 2, 3, 4, 5}, K = 4
Output: 2 3 4 5 1 

Algorithm: The given problem can be solved by reversing subarrays. Below steps can be followed to solve the problem:

• Reverse all the array elements from 1 to N -1
• Reverse the array elements from 1 to K – 1
• Reverse the array elements from K to N -1

C++

// C++ implementation for the above approach

#include <bits/stdc++.h>
using namespace std;

// Function to rotate the array
// to the right, K times
void RightRotate(int Array[], int N, int K)
{

    // Reverse all the array elements
    reverse(Array, Array + N);

    // Reverse the first k elements
    reverse(Array, Array + K);

    // Reverse the elements from K
    // till the end of the array
    reverse(Array + K, Array + N);

    // Print the array after rotation
    for (int i = 0; i < N; i++) {

        cout << Array[i] << " ";
    }

    cout << endl;
}

// Driver code
int main()
{

    // Initialize the array
    int Array[] = { 1, 2, 3, 4, 5 };

    // Find the size of the array
    int N = sizeof(Array) / sizeof(Array[0]);

    // Initialize K
    int K = 4;

    // Call the function and
    // print the answer
    RightRotate(Array, N, K);

    return 0;
}

Java

/*package whatever //do not write package name here */
import java.io.*;
class GFG
{

    // Function to rotate the array
    // to the right, K times
    static void RightRotate(int[] Array, int N, int K)
    {

        // Reverse all the array elements
        for (int i = 0; i < N / 2; i++) {
            int temp = Array[i];
            Array[i] = Array[N - i - 1];
            Array[N - i - 1] = temp;
        }

        // Reverse the first k elements
        for (int i = 0; i < K / 2; i++) {
            int temp = Array[i];
            Array[i] = Array[K - i - 1];
            Array[K - i - 1] = temp;
        }

        // Reverse the elements from K
        // till the end of the array
        for (int i = 0; i < (N-K) / 2; i++) {
            int temp = Array[(i + K)];
            Array[(i + K)] = Array[(N - i - 1)];
            Array[(N - i - 1)] = temp;
        }

        // Print the array after rotation
        for (int i = 0; i < N; i++) {

            System.out.print(Array[i] + " ");
        }

        System.out.println();
    }

    // Driver code
    public static void main(String[] args)
    {

        // Initialize the array
        int Array[] = { 1, 2, 3, 4, 5 };

        // Find the size of the array
        int N = Array.length;

        // Initialize K
        int K = 4;

        // Call the function and
        // print the answer
        RightRotate(Array, N, K);
    }
}

// This code is contributed by maddler.

Python3

# Python program for the above approach
import math

# Function to rotate the array
# to the right, K times
def RightRotate(Array, N, K):

    # Reverse all the array elements
    for i in range(math.ceil(N / 2)):
        temp = Array[i]
        Array[i] = Array[N - i - 1]
        Array[N - i - 1] = temp

    # Reverse the first k elements
    for i in range(math.ceil(K / 2)):
        temp = Array[i]
        Array[i] = Array[K - i - 1]
        Array[K - i - 1] = temp

    # Reverse the elements from K
    # till the end of the array
    for i in range(math.ceil((N-K) / 2)):
        temp = Array[(i + K)]
        Array[(i + K)] = Array[(N - i - 1)]
        Array[(N - i - 1)] = temp

    # Print the array after rotation
    for i in range(N):
        print(Array[i], end=" ")


# Driver Code
arr = [1, 2, 3, 4, 5]
N = len(arr)
K = 4

# Call the function and
# print the answer
RightRotate(arr, N, K)

# This code is contributed by Saurabh Jaiswal

C#

// C# program for the above approach
using System;
class GFG
{
    // Function to rotate the array
    // to the right, K times
    static void RightRotate(int []Array, int N, int K)
    {

        // Reverse all the array elements
        for (int i = 0; i < N / 2; i++) {
            int temp = Array[i];
            Array[i] = Array[N - i - 1];
            Array[N - i - 1] = temp;
        }

        // Reverse the first k elements
        for (int i = 0; i < K / 2; i++) {
            int temp = Array[i];
            Array[i] = Array[K - i - 1];
            Array[K - i - 1] = temp;
        }

        // Reverse the elements from K
        // till the end of the array
        for (int i = 0; i < (N-K) / 2; i++) {
            int temp = Array[(i + K)];
            Array[(i + K)] = Array[(N - i - 1)];
            Array[(N - i - 1)] = temp;
        }

        // Print the array after rotation
        for (int i = 0; i < N; i++) {

            Console.Write(Array[i] + " ");
        }
    }

    // Driver code
    public static void Main()
    {

        // Initialize the array
        int []Array = { 1, 2, 3, 4, 5 };

        // Find the size of the array
        int N = Array.Length;

        // Initialize K
        int K = 4;

        // Call the function and
        // print the answer
        RightRotate(Array, N, K);
    }
}
// This code is contributed by Samim Hossain Mondal.

Javascript

<script>
// Javascript program for the above approach

// Function to rotate the array
// to the right, K times
function RightRotate(Array, N, K)
{

    // Reverse all the array elements
    for (let i = 0; i < N / 2; i++) {
        let temp = Array[i];
        Array[i] = Array[N - i - 1];
        Array[N - i - 1] = temp;
    }

    // Reverse the first k elements
    for (let i = 0; i < K / 2; i++) {
        let temp = Array[i];
        Array[i] = Array[K - i - 1];
        Array[K - i - 1] = temp;
    }

    // Reverse the elements from K
    // till the end of the array
    for (let i = 0; i < (N-K) / 2; i++) {
        let temp = Array[(i + K)];
        Array[(i + K)] = Array[(N - i - 1)];
        Array[(N - i - 1) % N] = temp;
    }

    // Print the array after rotation
    for (let i = 0; i < N; i++) {
        document.write(Array[i] + " ");
    }
}

// Driver Code

let arr = [ 1, 2, 3, 4, 5 ];
let N = arr.length;
let K =4;

// Call the function and
// print the answer
RightRotate(arr, N, K);

// This code is contributed by Samim Hossain Mondal.
</script>

Output

2 3 4 5 1 

Time Complexity: O(N)  
Auxiliary Space: O(1)

Print array after it is right rotated K times using Recursion

Step-by-step approach:

• If “k” = 0, return the array “arr” and terminate the recursion.
• Else, move the last element to the first position and rotate the array “arr” to the right by one position by moving each element one position to the right.
• Recursively call the “rotateArray()” function with the same array “arr”, of size “n”, and k-1.
• Return the rotated array “arr” and terminate the recursion.

Below is the implementation of the above Recursive approach: 

C

#include <stdio.h>

// Function to rotate the array
void rotateArray(int arr[], int n, int k) {
    if (k == 0) {
        return;
    }

    // rotate the array to the right by one position
    int temp = arr[n-1];
    for (int i = n-1; i > 0; i--) {
        arr[i] = arr[i-1];
    }
    arr[0] = temp;

    // recursively rotate the remaining elements k-1 times
    rotateArray(arr, n, k-1);
}

// Driver code
int main() {
    int arr[] = {1, 3, 5, 7, 9};
    int n = sizeof(arr)/sizeof(arr[0]);
    int k = 2;

    rotateArray(arr, n, k);

    for (int i = 0; i < n; i++) {
        printf("%d ", arr[i]);
    }
    printf("\n");

    return 0;
}

// This code is contributed by  Vaibhav Saroj

C++

// C++ implementation for Print array after it is right
// rotated K times using Recursion

#include <bits/stdc++.h>
using namespace std;

// Function to rotate the array
void rotateArray(int arr[], int n, int k)
{
    if (k == 0) {
        return;
    }

    // Rotate the array to the right by one position
    int temp = arr[n - 1];
    for (int i = n - 1; i > 0; i--) {
        arr[i] = arr[i - 1];
    }
    arr[0] = temp;

    // Recursively rotate the remaining elements k-1 times
    rotateArray(arr, n, k - 1);
}

// Driver code
int main()
{
    int arr[] = { 1, 3, 5, 7, 9 };
    int n = sizeof(arr) / sizeof(arr[0]);
    int k = 2;

    rotateArray(arr, n, k);

    for (int i = 0; i < n; i++) {
        cout << arr[i] << " ";
    }
    cout << endl;

    return 0;
}

// This code is contributed by  Vaibhav Saroj

Java

import java.util.*;

public class Main {

    // Function to rotate the array
    public static void rotateArray(int[] arr, int n, int k) {
        if (k == 0) {
            return;
        }

        // rotate the array to the right by one position
        int temp = arr[n-1];
        for (int i = n-1; i > 0; i--) {
            arr[i] = arr[i-1];
        }
        arr[0] = temp;

        // recursively rotate the remaining elements k-1 times
        rotateArray(arr, n, k-1);
    }

    // Driver code
    public static void main(String[] args) {
        int[] arr = {1, 3, 5, 7, 9};
        int n = arr.length;
        int k = 2;

        rotateArray(arr, n, k);

        for (int i = 0; i < n; i++) {
            System.out.print(arr[i] + " ");
        }
        System.out.println();
    }
}

// This code is contributed by  Vaibhav Saroj

Javascript

function rotateArray(arr, n, k) {
  if (k === 0) {
    return;
  }

  // rotate the array to the right by one position
  const temp = arr[n-1];
  for (let i = n-1; i > 0; i--) {
    arr[i] = arr[i-1];
  }
  arr[0] = temp;

  // recursively rotate the remaining elements k-1 times
  rotateArray(arr, n, k-1);
}

// Driver code
const arr = [1, 3, 5, 7, 9];
const n = arr.length;
const k = 2;

rotateArray(arr, n, k);

console.log(arr); // Output: [ 7, 9, 1, 3, 5 ]


// This code is contributed by  Vaibhav Saroj

Output

7 9 1 3 5 

Time Complexity: O(k*n)
Auxiliary Space: O(k)