Array

Description:

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].

刷题还是习惯早上刷，现在脑子不灵光了，哎...

这题我想的很复杂，可以说和算法不沾边，看了Discuss照着写了一遍。

public class Solution {

    public void rotate(int[] nums, int k) {

        k %= nums.length;

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

        reverse(nums, 0, k-1);

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

    }

    public void reverse(int[]nums, int start, int end) {

        while (start < end) {

            int temp = nums[start];

            nums[start] = nums[end];

            nums[end] = temp;

            start++;

            end--;

        }

    }

}