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.

Solution: Binary search. O(lgn) eg. [4 5 6] -7- 8 1 2 3; 5 6 0 -1- [2 3 4]

class Solution {
public:
    int search(int A[], int n, int target) {
        int i = 0; 
        int j = n-1;
        while(i <= j) {
            int mid = i + (j-i)/2 ;
            if(A[mid] == target) return mid;
            if(A[i] <= A[mid]) {
                if(A[i] <= target && target < A[mid]) {
                    j = mid - 1;
                }
                else {
                    i = mid + 1;
                }
            }
            else {
                if(A[mid] < target && target <= A[j]) {
                    i = mid + 1;
                }
                else {
                    j = mid - 1;
                }
            }
        }
        return -1;
    }
};