Palindrome Number

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.

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负数不是回文数

使用O（1）的空间，所有不允许转化为字符串

有可能溢出

bool isPalindrome(int x) {
    if(x<0) return false;
    else if(x<10) return true;
    int digit=0;
    int y=x;
    while(y){
    	digit++;
    	y/=10;
    }
    int left=pow(10,digit-1);
    int right=1;
    while(left>right){
    	if(x/left%10 != x/right%10)
    		return false;
    	
    		
    	left/=10;
    	right*=10;
    }
    return true;
}