leetcode 9. Palindrome Number

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

bool isPalindrome(int x) {long long int xx = x;if (xx < 0)return false;if (xx<10)return true;int k = 0;while (xx>0){k++;xx /= 10;}xx = x;for (int i = 0; i<k / 2; i++){int r1 = xx % 10;int r2 = xx / pow(10, k - 1 - 2 * i);if (r1 != r2)return false;xx -= (r1 + r2*pow(10, k - 1 - 2 * i));xx /= 10;}return true;}

accepted