LeetCode Palindrome Number

题目：

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

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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.

class Solution {
public:
    //每次取最高位和最低位比较,然后将这两位去除
    bool isPalindrome(int x) {
        if(x < 0)
            return false;
        if(x == 0)
            return true;
        int base = 1;
        while(x/base >= 10) 
            base *= 10;
        while(x) {
            int left = x / base;
            int right = x % 10;
            if(left != right)
                return false;
            x = x - left * base;
            x /= 10;
            base /= 100;
        }
        return true;
    }
};