Determine whether an integer is a palindrome. Do this without extra space.
Some hints:Could negative integers be palindromes? (ie, -1)
If you are thinking of converting the integer to string, note the restriction of using extra space.
You could also try reversing an integer. However, if you have solved the problem "Reverse Integer", you know that the reversed integer might overflow. How would you handle such case?
There is a more generic way of solving this problem.
和回文字符串的判断类似，只需要比较对应的位是否相同。public boolean isPalindrome(int x) { if (x < 0) return false; int div = 1; while (x / div >= 10) { div *= 10; } while (x != 0) { int l = x / div; int r = x % 10; if (l != r) return false; x = (x % div) / 10; div /= 100; } return true; }
Palindrome Number,布布扣,bubuko.com
原文地址：http://blog.csdn.net/u010378705/article/details/31749813
