9. Palindrome Number

Posted 2020-07-08

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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?

棰樼洰锛氬垽鏂暣鏁版槸涓嶆槸鍥炴枃鏁?/p>

 1 bool isPalindrome(int x) {
 2     int temp;
 3     int n = 0;
 4     temp = x;
 5     if(x < 0)
 6         return 0;
 7     while(temp)
 8     {
 9         n = n*10 + temp % 10;           
10         temp = temp /10;
11     }
12     return (n == x);
13 }