Search in Rotated Sorted Array

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.

(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).

You are given a target value to search. If found in the array return its index, otherwise return -1.

You may assume no duplicate exists in the array.

代码如下：

public class SearchInRotatedSortedArray {public int search(int[] nums,int target){int n = nums.length;         if(nums == null || n <=0)            return -1;        int lo = 0, hi = n-1;while(lo<hi){int mid = (lo + hi) / 2;if(nums[mid] > nums[hi])lo = mid + 1;else hi = mid;}int rot = lo;//找到lo==hi时，是最小数的位置，也是旋转的位数lo = 0;hi = n-1;while(lo<hi){int mid = (lo+hi)/2;int realmid = (mid+rot)%n;if(nums[realmid]==target)return realmid;if(nums[realmid]<target)lo=mid+1;elsehi = mid-1;}return -1;}}