Determine whether an integer is a palindrome. Do this without extra space. http://oj.leetcode.com/problems/palindrome-number/

isPalindrome.cpp

// PalindromeNumber.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <math.h>

#include <iostream>

using namespace std;

class Solution 
{
public:
	// Determine whether an integer is a palindrome. Do this without extra space.
	bool isPalindrome(int x) 
	{
		// 2147483647

		if (x < 0)
			return false;

		int i = 0;
		int j = 9;
		bool started = false;

		while (i < j)
		{
			int left = (x / (int)pow(10, j)) % 10;
			if ((left == 0) && !started)
			{
				j--;
				continue;
			}
			else
			{
				started = true;
			}

			int right = (x / (int)pow(10, i)) % 10;

			if (left != right)
				return false;

			j--;
			i++;
		}

		return true;
	}
};


int _tmain(int argc, _TCHAR* argv[])
{
	Solution s;
	int input;
	bool result;

	input = 1;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result?"true":"false") << endl;

	input = -1;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 0;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 11;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 121;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 12;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 123;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 1221;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 12321;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 1000001;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;

	input = 1000110001;
	result = s.isPalindrome(input);
	cout << input << " -- " << (result ? "true" : "false") << endl;



	return 0;
}