9. Palindrome Number - Easy

前往題目

想法

• 很久以前做過的題目，只記得轉成string，忘了不轉要怎麼弄

思路

1. 用mod特性建立x的reverse
2. 比較reversed x和x是否相等

Code

class Solution {
    public boolean isPalindrome(int x) {
        // Negative number is always false
        if(x < 0){
            return false;
        }
        
        int xx = x; // Temp for x
        int y = 0; // Reverse order

        while(xx > 0){
            // Last number of xx
            int lastNum = xx % 10;
            // remove recorded num
            xx /= 10;

            // Make num from the first digit
            y = y * 10 + lastNum;

        }

        return x==y;
    }
}