Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.
Example 1:
Input: 121 Output: true
Example 2:
Input: -121 Output: false Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
Example 3:
Input: 10 Output: false Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
Follow up:
Coud you solve it without converting the integer to a string?
class Solution(object):
def isPalindrome(self, x):
"""
:type x: int
:rtype: bool
"""
if x < 0: return False
s = str(x)
i, j = 0, len(s)-1
while i<j:
if s[i] != s[j]:
return False
i += 1
j -= 1
return True
不使用string的话，还是比较巧妙的：
class Solution(object):
def isPalindrome(self, x):
"""
:type x: int
:rtype: bool
"""
if x < 0: return False
num = x
y = 0
while x != 0:
y = y*10 + x%10
x /= 10
return y == num
原文：https://www.cnblogs.com/bonelee/p/9346154.html