189. Rotate Array 旋转数组

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.

此题有多种解法，ps链接

class Solution {

public:    void rotate(vector<int>& nums, int k) {        //旋转两次        int n=nums.size();        k=k%n;        if(k!=0){        reverse(nums.begin(),nums.begin()+n-k);        reverse(nums.begin()+n-k,nums.end());        reverse(nums.begin(),nums.end());        }    }};