问如何在函数参数中使用类

EN

 #include<iostream>
    #include<cstdlib>
    #include<string>
    using namespace std;
    class Address
    {
   private:
      string home;
      string street;
      string apt;
      string city;
      string state;
      string zip;

   public:

      Address();

     string getHome() const;
    string getStreet() const;

      string getApt() const;

      string getCity() const;

      string getState() const;

      string getZip() const;

      void output() const;

      void input();
};

class contact{
private:
    string fn;  
    string ln;
    Address address;
    string email;
    string number;
public:
    void input();
    void output();
    void setname(string f_n, string l_n);
    void setaddress(Address home);
    void setemail(string emaila);
    void setnumber(string num);
    string getname();
    string getAddress();
    string getemail();
    string getnumber();

contact();
contact(string f_n, string l_n, Address home,string emaila,string num);

};
void menu(string opt);
int main(){
        string opt="";
     contact c;
     c.input();
     menu(opt);
     c.output();

cout<<"input up to 10 contacts, type quit to stop if less than 10: "<<endl;

return 0;
}
void menu(string opt){
cout<<"Choose(type) a Menu: search | display all(show) | exit'"<<endl;
cin>>opt;
if(opt=="search")cout<<"write a function that index"<<endl;
else if(opt=="show")cout<<"write a function that display all: "<<endl;
else if(opt=="exit")exit(0);
}
contact::contact(){ 
    fn="";  ln="";  Address address;    email="";   number="";
}
contact::contact(string f_n, string l_n, Address address,string emaila,string num){
fn= f_n; ln= l_n; address ="" ;email= emaila;number= num;
}

void contact::input(){
 for (int i=1; i<=10;i++){//allow 10 contacts
cout<<"fn and ln separate by a space: ";
cin>>fn>>ln;
cout<<"address: ";
Address.input();
cout<<"email: ";
cin>>email;
cout<<"phone number: ";
cin>>number;
}
}
void contact::output(){
cout<<"name: "<<fn<<" "<<ln<<" address "<<Address.output();<<" email: "<<email<<"         digits "<<number<<endl;
}
void contact::setname(string f_n, string l_n){
fn= f_n; ln= l_n;
}

void contact::setemail(string emaila){
email= emaila;
}
void contact::setnumber(string num){
number= num;
}
string contact::getAddress(){
return Address address;
}
string contact::getname(){
return fn, ln;
}

string contact::getemail(){
return email;
}
string contact::getnumber(){
return number;
}