Palindrome Number
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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