LeetCod-Search in Rotated Sorted Array （Java）

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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.

Your algorithm’s runtime complexity must be in the order of O(log n).

Example 1:

Input: nums = [4,5,6,7,0,1,2], target = 0 Output: 4 Example 2:

Input: nums = [4,5,6,7,0,1,2], target = 3 Output: -1

在旋转数组中查找数字，数字是唯一的

class Solution {
    public int search(int[] nums, int target) {
        int left = 0;
        int right = nums.length -1;
        if(right < 0) {
            return -1;
        }
        int mid = right / 2;
        while(nums[mid] != target) {
            
            if(nums[mid] > nums[right]) { // 左边是有序的
                if(nums[mid] < target || nums[left] > target) {
                    left = mid + 1;
                } else{
                    right = mid -1;
                }
            } else if(nums[left] > nums[mid]){  //右边是有序的 
                if(nums[mid] > target || nums[right] < target) {
                    right = mid -1;
                } else {
                    left = mid + 1;
                }
            } else { // 整体是有序的
                if(nums[mid] < target) {
                    left = mid + 1;
                } else {
                    right = mid -1;
                }
            }
            if(left > right) {
                return -1;
            }
            int temp = (right -left) / 2;
            
            mid = left + temp;
        }
        return mid;
    }
    
}