Palindrome Number

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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:

Could you solve it without converting the integer to a string? 

Solution:

One approach is to convert the number to string and then compare the string with it's reverse.

Second approach which is also the answer to the follow-up question is to reverse the number and then compare the original and the reversed number.


Time Complexity : O(log x)

Space Complexity: O(1)

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