491 · Palindrome Number - LintCode

# Description

Check a positive number is a palindrome or not.

A palindrome number is that if you reverse the whole number you will get exactly the same number.

It's guaranteed the input number is a 32-bit integer, but after reversion, the number may exceed the 32-bit integer.

# Example

Example 1:

Input:11
Output:true

Example 2:

Input:1232
Output:false
Explanation:
1232!=2321

	public class Solution {
	/**
	* @param num: a positive number
	* @return: true if it's a palindrome or false
	*/
	public boolean isPalindrome(int num) {

	String newX = x+"";
	StringBuilder res = new StringBuilder();
	for (int i = newX.length() - 1; i >= 0; i--) {
	res.append(newX.charAt(i));
	}

	return res.toString().equals(newX);


	}
	}

	class Solution {
	public boolean isPalindrome(int x) {
	if (x < 0) return false;
	StringBuilder s = new StringBuilder();
	s.append(x);
	int left = 0;
	int right = s.length() - 1;
	while (left < right) {
	if (s.charAt(left) != s.charAt(right)) {
	return false;
	}
	left++;
	right--;
	}
	return true;

	}
	}