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].

 

public class Solution {
    public void rotate(int[] nums, int k) {
        if (nums == null || k <= 0) {
        	return;
        }
        k = k % nums.length;
        k = nums.length - k;
        reverse(nums, 0, k - 1);
        reverse(nums, k, nums.length - 1);
        reverse(nums, 0, nums.length - 1);
    }

	private void reverse(int[] nums, int s, int e) {
		// TODO Auto-generated method stub
		int tmp = 0;
		while (s < e) {
			tmp = nums[s];
			nums[s] = nums[e];
			nums[e] = tmp;
			s++;
			e--;
		}
	}
}