```
# 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
"""
s=1
e=n+1
num=1
while s<e:
num=(s+e)>>1
res=guess(num)
if res==0:
return num
```

```
elif res<0:
e=num
else:
s=num+1
return s
```