LeetCode 33 Search in Rotated Sorted Array（在旋轉排序數組中搜索）（*）

翻譯

假定一個數組在一個我們預先不知道的軸點旋轉。

例如，0 1 2 4 5 6 7可能會變為4 5 6 7 0 1 2。

給你一個目標值去搜索，如果找到了則返回它的索引，否則返回-1。

你可以假定沒有重復的元素存在於數組中。

原文

Suppose a sorted array 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.

代碼

class Solution {
public:
    int search(vector& nums, int target) {
        int l = 0, r = nums.size()-1;
        while (l<=r) {
            int mid = (r-l)/2+l;
            if (nums[mid] == target)
                return mid;
            if (nums[mid] < nums[r]) {
                if (nums[mid]