【leetcode】Search in Rotated Sorted Array

 1 class Solution {
 2 public:
 3     int search(int A[], int n, int target) {
 4        
 5         int left=0;
 6         int right=n-1;
 7         int mid;
 8         while(left<=right)
 9         {
10             mid=(left+right)/2;
11            
12             if(A[mid]==target) return mid;
13            
14             if(A[left]<A[mid])//left
15             {
16                 if(A[left]<=target&&target<A[mid])
17                 {
18                     right=mid-1;
19                 }
20                 else
21                 {
22                     left=mid+1;
23                 }
24             }
25             else if(A[left]>A[mid])//right
26             {
27                 if(A[mid]<target&&target<=A[right])
28                 {
29                     left=mid+1;
30                 }
31                 else
32                 {
33                     right=mid-1;
34                 }
35             }
36             else
37             {
38                 //最后一个判断语句可以一起放到第一个语句里，if(A[left]<=A[mid])
39                 left=mid+1;
40             }
41            
42         }
43         return -1;
44     }
45 };