LeetCode 189 - Rotate Array - 题解/Solution

https://leetcode.com/problems/rotate-array/

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/**
* 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.
*
* @author dongyuxi
*
*/
public class Solution {
public void rotate(int[] nums, int k) {
if (null == nums) {
return;
}

int length = nums.length;
if (k < 0) {
k = length - (-k) % length;
} else {
k = k % length;
}
reverse(nums, 0, length - k - 1);
reverse(nums, length - k, length - 1);
reverse(nums, 0, length - 1);
}

private void reverse(int[] nums, int start, int end) {
while (start < end) {
int temp = nums[start];
nums[start] = nums[end];
nums[end] = temp;
start++;
end--;
}
}
}


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