9. Palindrome Number
Last updated
Last updated
/**
* Time complexity : O(log10(n)). We divided the input by 10 for every iteration,
* so the time complexity is O(log10(n)).
* Space complexity : O(1)
*/
class Solution {
public boolean isPalindrome(int n) {
if(n < 0 || (n % 10 == 0 && n != 0)) {
return false;
}
int revertedNumber = 0;
while(revertedNumber < n) {
revertedNumber = (revertedNumber*10) + (n%10);
n /= 10;
}
return (revertedNumber == n) || (n == revertedNumber/10);
}
}