7--Reverse-Integer

https://leetcode.com/problems/reverse-integer/description/
输入: 32位有符号 int
输出: 逆序
思路:
循环取余就可以实现了,需要注意溢出的情况

class Solution {
    public int reverse(int x) {
        int t = x;
        int num = 0;
        while(t!=0){
            int temp = num*10 + t%10;
            if((temp-t%10)/10 != num){
                return 0;
            }
            num = temp;
            t=t/10;
        }
        return num;
    }
}