leetcode - Search in Rotated Sorted Array

 

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.
        if (n<=0)
            return -1;
        int left = 0, right = n-1;
        int middle;
        while (left<=right){
            if (A[left]==target)
                return left;
            if (A[right]==target)
                return right;
            middle = (left+right)/2;
            if (A[middle]==target)
                return middle;
            if (A[middle]>target){
                if (A[right]>target){
                    if (A[middle]>A[right])
                        left = middle+1;
                    else right = middle-1;
                }
                else right = middle-1;
            }
            if (A[middle]<target){
                if (A[right]>target)
                    left = middle+1;
                else {
                    if (A[right]>A[middle])
                        right = middle-1;
                    else 
                        left = middle+1;
                }
            }
        }
        return -1;
    }
};