LeetCode Rotate Array(数组的旋转)

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]

.

题意：给出一个数组，让其右移k 位，求新的数组

思路：先将[0,len-1]翻转，再[0,k-1]之间翻转，[k,len-1]之间翻转

代码如下

public class Solution
{
public void rotate(int[] nums, int k)
{
int len = nums.length;
int i = 0, j = len - 1;
while (i < j)
{
int tmp = nums[i];
nums[i] = nums[j];
nums[j] = tmp;
i++;
j--;
}

if (k > len) k -= len;

i = 0;
j = k - 1;
while (i < j)
{
int tmp = nums[i];
nums[i] = nums[j];
nums[j] = tmp;
i++;
j--;
}

i = k;
j = len - 1;
while (i < j)
{
int tmp = nums[i];
nums[i] = nums[j];
nums[j] = tmp;
i++;
j--;
}
}
}