reverse integer

Reverse digits of an integer.

Example1: x = 123, return 321

Example2: x = -123, return -321

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Have you thought about this?
Here are some good questions to ask before coding. Bonus points for you if you have already thought through this!
If the integer's last digit is 0, what should the output be? ie, cases such as 10, 100.
Did you notice that the reversed integer might overflow? Assume the input is a 32-bit integer, then the reverse of 1000000003 overflows. How should you handle such cases?
For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.

简单易懂但是overflow了：

public int reverse(int x) {
        int res=0;  
        while(x!=0) {  
            res = res*10 + x%10;      
            x /=10;  
        }  
          
        return res;   
    }

ac:

public class Solution {
    public int reverse(int x) {
        int res=0;  
  
        while(x!=0) {  
            int tail = x%10;
            int newResult = res*10 + tail;
            //newResult-tail/10 得到的时原来的res,如果没有overflow，两者应该相等
            if((newResult-tail)/10 != res){
                return 0;
            }
            res = newResult;      
            x /=10;  
        }  
        return  res;   
    }  
}