# Guess Number Higher or Lower

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.

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

Constraints:

• `1 <= n <= 231 - 1`
• `1 <= pick <= n`

SOLUTION:

``````# The guess API is already defined for you.
# @return -1 if my number is lower, 1 if my number is higher, otherwise return 0
# def guess(num: int) -> int:

class Solution:
def guessNumber(self, n: int) -> int:
beg = 1
end = n
if guess(beg) == 0:
return beg
if guess(end) == 0:
return end
while beg <= end:
mid = (beg + end) // 2
curr = guess(mid)
if curr == 0:
return mid
elif curr == -1:
end = mid
else:
beg = mid
``````