guessNumber.py

'''
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'll tell you whether the number is higher or lower.

You call a pre-defined API guess(int num) which returns 3 possible results (-1, 1, or 0):

-1 : My number is lower
 1 : My number is higher
 0 : Congrats! You got it!
Example:
n = 10, I pick 6.
Return 6.
'''
"""
        :type n: int
        :rtype: int
        """
# The guess API is already defined for you.
# @param num, your guess
# @return -1 if my number is lower, 1 if my number is higher, otherwise return 0
# def guess(num):

class Solution(object):
    def guessNumber(self, n):
        low = 1
        high = n
        if low == high:
            return low
        mid = (low+high)//2
        while guess(mid) != 0:
            if guess(mid) == 1:
                low = mid
            elif guess(mid) == -1:
                high = mid
            mid = (low+high)//2
            if high == low + 1:
                return high if guess(high) == 0 else low
        return mid