leetcode[33]Search in Rotated Sorted Array

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.

class Solution {
public:

    int search(int A[], int n, int target) {
    if(A==NULL||n==0)return -1;
    int left=0,right=n-1;
    int mid;
    while(left<=right)
    {
        mid=(left+right)/2;
        if(A[mid]==target)return mid;
        if (A[left]<=A[mid])
        {
            if (target>=A[left]&&target<A[mid])
                right=mid-1;
            else left=mid+1;
        }
        else
        {
            if (target>A[mid]&&target<=A[right])
                left=mid+1;
            else right=mid-1;
        }
    }
    return -1;
    }
/*
    int search(int A[], int n, int target) {
        if(A==NULL||n==0)return -1;
        int left=0, right=n-1;
        int mid;
        while(left<=right)
        {
            mid=(left+right)/2;
            if(A[mid]==target)return mid;
            if(A[mid]>=A[left])
            {
                if(A[mid]<target)left=mid+1;
                else
                {
                    if(target>=A[left])right=mid-1;
                    else left=mid+1;
                }
            }
            else
            {
                if(target<A[mid])right=mid-1;
                else 
                {
                    if (target<=A[right])left=mid+1;
                    else right=mid-1;
                }
            }
        }
        return -1;
    }
*/
};