package PalindromeNumber;

/**

* User: Danyang

* Date: 1/15/2015

* Time: 12:44

* Determine whether an integer is a palindrome. Do this without extra space.

*/

public class Solution {

/**

* TESTING

* OVERFLOW

* @param x

* @return

*/

public boolean isPalindrome(int x) {

if(x<0)

return false;

long sig = 1; // int overflow

for(int i=x; i>0; i/=10)

sig *= 10;

sig /= 10;

// for(int i=x; i>=10; i=i%(sig)/10, sig/=100) {

// if(i%10!=i/sig)

// return false;

// }

int acc = 10;

for(int i=x; sig>=acc; sig/=10, acc*=10) {

long l = i/sig%10;

long r = i%acc/(acc/10);

if(r!=l)

return false;

}

return true;

}

public static void main(String[] args) {

System.out.println(new Solution().isPalindrome(1000000001));

System.out.println(new Solution().isPalindrome(100031));

System.out.println(new Solution().isPalindrome(12321));

}

}