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?
如果是回文数字，则反转之后数字相等。可以再进一步，不需要完全反转，只需要反转一半即可，反转一般，反转数字跟原始数字就相等或者相近了。
link:{sourcedir}/_0009_PalindromeNumber.java[role=include]