7. Reverse Integer

Posted 2020-10-11 andywu

Reverse digits of an integer.

Example1: x = 123, return 321
Example2: x = -123, return -321

题目含义翻转一个整数

1     public int reverse(int x) {
2         int res = 0;
3         while (x != 0) {
4             if (Math.abs(res) > Integer.MAX_VALUE / 10) return 0; //防止接下来的res*10超过Integer.MAX_VALUE
5             res = res * 10 + x % 10;
6             x /= 10;
7         }
8         return res;        
9     }