LeetCode 9. Palindrome Number 回文数 Python

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.

题目：判断一个是否是回文数
思路：很直观的做法，首先计算输入的number的位数，然后从两边分别比较，一旦发现不对称就返回false。

class Solution(object):
    def isPalindrome(self, x):
        """
        :type x: int
        :rtype: bool
        """
        if x<0:
            return False

        digits=1
        while(x/digits>=10):
            digits*=10

        num=x
        while(digits>1):
            right=num%10
            left=num/digits
            if right!=left:
                return False
            else:
                num=(num%digits)/10
                digits/=100

        return True

运行结果：279ms，beat 78% 的solution