Rotate an array

Problem: Given an array, rotate the array to the right by k steps, where k is non-negative.

Example (taken from leetcode):

Input: nums = [1,2,3,4,5,6,7], k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]

Approach: Reverse the whole array. Reverse 1st k elements and then reverse the rest of n-k elements. Now k could be more than n so we can initialize k as k = k mod n.

Implementation in C#:

        public static void Rotate(int[] nums, int k)

        {

            if (nums?.Length <= 1)

            {

                return;

            }

            k %= nums.Length;

            reverse(nums, 0, nums.Length - 1);

            reverse(nums, 0, k - 1);

            reverse(nums, k, nums.Length - 1);

        }

        private static void reverse(int[] nums, int startIndex, int endIndex)

        {

            for (int i = startIndex, j = endIndex; i < j; ++i,--j)

            {

                int temp = nums[i];

                nums[i] = nums[j];

                nums[j] = temp;

            }

        }

Complexity: O(n)