Leetcode: Rotate Array

Rotate an array of n elements to the right by k steps.

For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4].

Note:
Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.

Code (Java):

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public class Solution {     public void rotate(int[] nums, int k) {         if (nums == null || nums.length <= 1 || k <= 0) {             return;         }                   // Step 1: swap each element of the array         int i = 0;         int j = nums.length - 1;         while (i < j) {             swap(nums, i, j);             i++;             j--;         }                   k %= nums.length;                   // Step 2: swap the first k elements         i = 0;         j = k - 1;         while (i < j) {             swap(nums, i, j);             i++;             j--;         }                   // Step 3: swap the rest of k elements         i = k;         j = nums.length - 1;         while (i < j) {             swap(nums, i, j);             i++;             j--;         }     }           private void swap(int[] nums, int i, int j) {         int tmp = nums[i];         nums[i] = nums[j];         nums[j] = tmp;     } }