#include<iostream>

using namespace std;

class DivideByZeroException{

    const char* message; //异常信息

    public:

        DivideByZeroException():message("divided by zero"){

        }

        const char* what(){

            return message;

        }

};

//除法函数

double testdiv(int num1,int num2){

    if(num2==0){

        throw DivideByZeroException();

    }

    return (double)num1/num2;

}

int main(){

    int num1,num2;

    double res;

    cout<<"please input two integers:"<<endl;

    while(cin>>num1>>num2){

        try{

            res=testdiv(num1,num2);

            cout<<"the res is :"<<res<<endl;

        }

        catch(DivideByZeroException ex){

            cout<<"error"<<ex.what()<<endl;

            break;

        }

        cout<<"\n please input two integers:";

    }

    return 0;

}