Rotate Array.java

class Solution {
    public void rotate(int[] nums, int k) {
        reverse(nums , 0 , nums.length-1);
        reverse(nums , 0 , k-1);
        reverse(nums , k , nums.length -1);
    }
    
    public static void reverse(int[] arr , int start , int end){
        while(start<end){
            int temp = arr[start];
            arr[start] = arr[end];
            arr[end] = temp;
            start++;
            end--;
        }
    }
}