374. Guess Number Higher or Lower
Easy
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 > pick
).1
: Your guess is lower than the number I picked (i.e.num < pick
).0
: your guess is equal to the number I picked (i.e.num == pick
).
Return the number that I picked.
# The guess API is already defined for you.
# @param num, your guess
# @return -1 if num is higher than the picked number
# 1 if num is lower than the picked number
# otherwise return 0
# def guess(num: int) -> int:
class Solution:
def guessNumber(self, n: int) -> int:
return self.helper(1, n)
def helper(self, low, high):
mid = low + (high - low) // 2
n = guess(mid)
if n < 0:
return self.helper(low, mid)
elif n == 0:
return mid
else:
return self.helper(mid + 1, high)