LeetCode-189. Rotate Array

Given an array, rotate the array to the right by k steps, where k is non-negative.

Example 1:

Input: ​​[1,2,3,4,5,6,7]​​ and k = 3 Output: ​​[5,6,7,1,2,3,4]​​ Explanation: rotate 1 steps to the right: ​​[7,1,2,3,4,5,6]​​​ rotate 2 steps to the right: ​​​[6,7,1,2,3,4,5] ​​​rotate 3 steps to the right: ​​[5,6,7,1,2,3,4]​​

Example 2:

Input: ​​[-1,-100,3,99]​​ and k = 2 Output: [3,99,-1,-100] Explanation: rotate 1 steps to the right: [99,-1,-100,3] rotate 2 steps to the right: [3,99,-1,-100]

题解：

class Solution {
public:
    void rotate(vector<int>& nums, int k) {
        int n = nums.size();
        if (n <= 1) {
            return;
        }
        k %= n;
        reverse(nums.begin(), nums.end());
        reverse(nums.begin(), nums.begin() + k);
        reverse(nums.begin() + k, nums.end());
    }
};