Palindrome Number (Java)

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.

负数不是回文数

注意接近INT最大值的数的翻转有可能会溢出，最好定义成long

Source

public static boolean isPalindrome(int x) {int i,j;long k = x, temp,num = 0;if(x < 0) return false;while(k != 0){temp = k % 10;num = num * 10 + temp;k = k / 10;}if(num == x) return true;else return false;}