Leetcode - Palindrome Number Solution
Poor Man
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- 1 min read
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- 145 words
Given an integer x, return true if x is palindrome integer.
An integer is a palindrome when it reads the same backward as forward. For example, 121 is palindrome while 123 is not.
Example 1:
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Input: x = 121
Output: trueExample 2:
Text
Input: x = -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:
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Input: x = 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.Example 4:
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Input: x = -101
Output: falseConstraints:
-231 <= x <= 231 - 1
Follow up: Could you solve it without converting the integer to a string?
Solution in Python#
Python
class Solution:
def isPalindrome(self, x: int) -> bool:
number = x
reverse_number = 0
while number>0:
remainder = number %10
number = (number - remainder)//10
reverse_number= reverse_number*10+remainder
return x == reverse_number