LeetCode Rotate Array

Rotate Array Total Accepted: 12759 Total Submissions: 73112 My Submissions Question Solution
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.

题意：循环数组，n代表数组的长度，k代表向右移动的次数。
解法一：

class Solution {
public:
    void rotate(int nums[], int n, int k) {
        if(n==0)return;
        k=k%n;//当k大于n的时候，n次循环会回到初始位置，因此，可以省略若干次
        if (k == 0) return;  
        int *s=new int[k];//为了一步到位的展开移动，申请k个额外空间用于保存被移出去的元素
        for(int i=0;i
   
    =0;--j) nums[j+k]=nums[j];//移动 for(int i=0;i
    
   

需要额外空间O（k%n）
33 / 33 test cases passed.
Status: Accepted
Runtime: 29 ms

解法二（网络获取）：
三次翻转法，第一次翻转前n-k个，第二次翻转后k个，第三次翻转全部。

class Solution { public: void rotate(int nums[], int n, int k) { if(n==0)return ; k=k%n; if(k==0)return ; reverse(nums,n-k,n-1); reverse(nums,0,n-k-1); reverse(nums,0,n-1); } void reverse(int nums[],int i,int j) { for(;i
    

33 / 33 test cases passed.
Status: Accepted
Runtime: 26 ms