374. Guess Number Higher or Lower

time: O(logn)

space:O(1)

class Solution {
    public int search(int[] nums, int target) {
        int left = 0;
        int right = nums.length - 1;
        
        while (left <= right) {
            int mid = (left + right) >> 1;
            if (nums[mid] == target) {
                return mid;
            }
            // start mid right
            if (nums[left] <= nums[mid]) {
                if ( target <= nums[mid] && target >= nums[left]) {
                    right = mid - 1;
                } else {
                    left = mid + 1;
                }
            } else {
                if ( target >= nums[mid] && target <= nums[right]) {
                    left = mid + 1;
                } else {
                    right = mid - 1;
                }
            }
            
        }
        return -1;
    }
}