When I read "no extra space", I took it literally...

In retrospect, that was foolish of me.

Anyways..

```
def isPalindrome(self, x):
"""
:type x: int
:rtype: bool
"""
if x<0:
return False
if x == 0:
return True
for i in range(0, int((math.floor(math.log(x,10))+1)//2 )):
if x // 10 ** i%10 != (x // 10**(int((math.floor(math.log(x,10))))-i))%10:
return False
return True
```