Leetcode(Search in Rotated Sorted Array II )

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.

Follow up for "Search in Rotated Sorted Array":

What if duplicates are allowed?

Would this affect the run-time complexity? How and why?

Write a function to determine if a given target is in the array.

代码：

class Solution {
public:
bool search(int A[], int n, int target) {
if(A == NULL)
return false;
return search(A, 0, n- 1, target);
}
bool search(int A[], int start, int end, int target)
{

while(start <= end)
{
int mid = start + ((end - start) >> 1);
if(A[mid] == target)
return true;
while(A[mid] == A[start] && A[mid] == A[end])
{
++start;
--end;
}
if(A[mid] >= A[start])
{
if(target >= A[start] && target < A[mid])
end = mid - 1;
else
start = mid + 1;
}
else
{
if(target > A[mid] && target <= A[end])
start = mid + 1;
else
end = mid - 1;
}
}
return false;
}
};