Loop Array Hash Map Counting Prefix Sum
Intermediate Level

Implement the rotateArrayRightK method that returns the array after rotating it k positions to the right.

The input contains an integer array nums, its length size, and an integer k. Your task is to rotate the array to the right by k positions and return the rotated array.

In a right rotation, elements from the end move to the beginning. For example, rotating [1,2,3,4,5] right by 2 gives [4,5,1,2,3].

Example 1
Input:
nums (int[]) = [1,2,3,4,5]
size (int) = 5
k (int) = 2
Return:
(int[]) [4,5,1,2,3]
Example 2
Input:
nums (int[]) = [1,2,3]
size (int) = 3
k (int) = 1
Return:
(int[]) [3,1,2]
Example 3
Input:
nums (int[]) = [1,2]
size (int) = 2
k (int) = 2
Return:
(int[]) [1,2]

First reduce k using k % size, because rotating by the array length brings the array back to the same order.

One simple way is to split the array into two parts: the last k elements and the remaining first part. Place the last part first, followed by the first part.

If k becomes 0, return the array unchanged.

Pseudocode:

function rotateArrayRightK(nums, size, k):
    if size == 0:
        return nums
    k = k % size
    if k == 0:
        return nums
    result = empty array
    for i from size - k to size - 1:
        add nums[i] to result
    for i from 0 to size - k - 1:
        add nums[i] to result
    return result
Run your code to see the result.