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.

[show hint]

Related problem: Reverse Words in a String II

Credits:
Special thanks to @Freezen for adding this problem and creating all test cases.

Analysis:

We can rotate string also like this.

Solution:

public class Solution {
    public void rotate(int[] nums, int k) {
        if (nums.length==0) return;
        
        int steps = k % nums.length;
        if (steps==0) return;
        
        swap(nums,0,nums.length-1);
        swap(nums,0,steps-1);
        swap(nums,steps,nums.length-1);
    }
    
    public void swap(int[] nums, int start, int end){
        while (start<end){
            int temp = nums[start];
            nums[start++] = nums[end];
            nums[end--] = temp;
        }
    }
}