Leetcode Question 374 'Guess Number Higher or Lower' in Java

We are playing the Guess Game. The game is as follows:

I pick a number from 1 to n. You have to guess which number I picked.

Every time you guess wrong, I will tell you whether the number I picked is higher or lower than your guess.

You call a pre-defined API int guess(int num), which returns three possible results:

-1: Your guess is higher than the number I picked (i.e. num greater than pick).
1: Your guess is lower than the number I picked (i.e. num less than pick).
0: your guess is equal to the number I picked (i.e. num == pick).
Return the number that I picked.



Example 1:

Input: n = 10, pick = 6
Output: 6
Example 2:

Input: n = 1, pick = 1
Output: 1
Example 3:

Input: n = 2, pick = 1
Output: 1