Javascript Program to Print array after it is right rotated K times

Given an Array of size N and a values K, around which we need to right rotate the array. How to quickly print the right rotated array?
Examples :

Input: Array[] = {1, 3, 5, 7, 9}, K = 2.
Output: 7 9 1 3 5
Explanation:
After 1st rotation - {9, 1, 3, 5, 7}
After 2nd rotation - {7, 9, 1, 3, 5}

Input: Array[] = {1, 2, 3, 4, 5}, K = 4.
Output: 2 3 4 5 1      

Approach:

1. We will first take mod of K by N (K = K % N) because after every N rotations array will become the same as the initial array. 
   
2. Now, we will iterate the array from i = 0 to i = N-1 and check, 
   • If i < K, Print rightmost Kth element (a[N + i -K]). Otherwise, 
     
   • Print array after ‘K’ elements (a[i – K]). 
     

Below is the implementation of the above approach. 

Javascript

// Javascript implementation of right rotation
// of an array K number of times

// Function to rightRotate array
function RightRotate(a, n, k)
{

    // If rotation is greater
    // than size of array
    k = k % n;

    for (let i = 0; i < n; i++) {
        if (i < k) {

            // Printing rightmost
            // kth elements
            document.write(a[n + i - k] + " ");
        }
        else {

            // Prints array after
            // 'k' elements
            document.write((a[i - k]) + " ");
        }
    }
    document.write("<br>");
}

// Driver code
let Array = [1, 2, 3, 4, 5];
let N = Array.length;
let K = 2;

RightRotate(Array, N, K);

// This code is contributed by gfgking.

Output:

4 5 1 2 3

Time complexity : O(n) 
Auxiliary Space : O(1)

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