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.
思考：二分搜索。
class Solution {
public:
int search(int A[], int n, int target) {
// IMPORTANT: Please reset any member data you declared, as
// the same Solution instance will be reused for each test case.
int left=0;
int right=n-1;
int mid;
while(left<=right)
{
mid=(left+right)>>1;
if(A[mid]==target) return mid;
else if(A[mid]>=A[left])
{
if(A[left]<=target&&target<=A[mid]) right=mid-1;
else left=mid+1;
}
else
{
if(A[mid]<=target&&target<=A[right]) left=mid+1;
else right=mid-1;
}
}
return -1;
}
};