LintCode: Recover Rotated Sorted Array

Given a rotated sorted array, recover it to sorted array in-place.

Example

[4, 5, 1, 2, 3] -> [1, 2, 3, 4, 5]

Challenge Expand 

Clarification Expand 

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Solution:
The key to the problem is to reverse the list. There are three steps. Take the example of [4, 5, 1, 2, 3]. 
Step 1: [4, 5]  -> [5, 4]
Step 2: [1, 2, 3] -> [3, 2, 1]
Step 3: [5, 4, 3, 2, 1] -> [1, 2, 3, 4, 5]

Code (Java):

/**
 * Copyright: NineChapter
 * - Algorithm Course, Mock Interview, Interview Questions
 * - More details on: http://www.ninechapter.com/
 */

import java.util.ArrayList;


public class Solution {
    /**
     * @param nums: The rotated sorted array
     * @return: The recovered sorted array
     */
    private void reverse(ArrayList<Integer> nums, int start, int end) {
        for (int i = start, j = end; i < j; i++, j--) {
            int temp = nums.get(i);
            nums.set(i, nums.get(j));
            nums.set(j, temp);
        }
    }

    public void recoverRotatedSortedArray(ArrayList<Integer> nums) {
        for (int index = 0; index < nums.size() - 1; index++) {
            if (nums.get(index) > nums.get(index + 1)) {
                reverse(nums, 0, index);
                reverse(nums, index + 1, nums.size() - 1);
                reverse(nums, 0, nums.size() - 1);
                return;
            }
        }
    }
}