278. First Bad Version; 374. Guess Number Higher or Lower

278. First Bad Version
# The isBadVersion API is already defined for you.
# @param version, an integer
# @return a bool
# def isBadVersion(version):

class Solution(object):
    def firstBadVersion(self, n):
        """
        :type n: int
        :rtype: int
        """
        left = 1
        right = n
        while left < right:
            mid = left + (right-left)/2
            if self.firstBadVersion(mid):
                right = mid
            else:
                left = mid+1
        return left

374. Guess Number Higher or Lower

# 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):
        """
        :type n: int
        :rtype: int
        """
        left = 1
        right = n
        while left < right:
            mid = left + (right-left)/2
            if guess(mid) == 1:
                left = mid + 1
            elif guess(mid) == -1:
                right = mid -1
            else:
                return mid
                break
        return left