Given a rotated sorted array, recover it to sorted array in-place.
Example
[4, 5, 1, 2, 3] -> [1, 2, 3, 4, 5]
Challenge
In-place, O(1) extra space and O(n) time.
Clarification
What is rotated array?
public class Solution { /** * @param nums: The rotated sorted array * @return: The recovered sorted array */ public void recoverRotatedSortedArray(ArrayList<Integer> nums) { // write your code 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; } } } public void reverse(ArrayList<Integer> nums, int start , int end){ for(int i = start, j = end ; i < j ; i++ , j--){ int tmp = nums.get(i); nums.set(i,nums.get(j)); nums.set(j,tmp); } } }