实验五

task.4

cpp

#include <iostream>
#include "Pets.hpp"
void play(MachinePets &obj) {
    std::cout << obj.get_nickname() << " says " << obj.talk() << std::endl;
}
 
void test() {
    PetCats cat("miku");
    PetDogs dog("da huang");
 
    play( cat );
    play( dog );
}
 
int main() 
{
    test();
}

hpp

#pragma once
#include <iostream>
#include <string>
using namespace std;
using std::string;
 
class MachinePets
{
public:
    MachinePets(const string name) : nickname{name} {}
    ~MachinePets() = default;
    string get_nickname() const { return nickname; }
    virtual string talk() = 0;
 
private:
    string nickname;
};
 
class PetCats : public MachinePets
{
 
public:
    PetCats(const string str) : MachinePets(str) {}
    ~PetCats() = default;
    string talk() { return "miao wu~"; }
};
 
class PetDogs : public MachinePets
{
public:
    PetDogs(const string s) : MachinePets(s) {}
    ~PetDogs() = default;
    string talk() { return "wang wang~"; }
};

task.5

cpp

#include <iostream>
#include <fstream>
#include <vector>
#include "Person.hpp"
 
void test() {
    using namespace std;
 
    vector<Person> phone_book;
    Person p;
 
    cout << "Enter person's contact until press Ctrl + Z" << endl;
    while(cin >> p)
        phone_book.push_back(p);
     
    cout << "\nupdate someone's contact: \n";
    phone_book.at(0).update_telephone();
    phone_book.at(0).update_email();   
     
    cout << "\ndisplay all contacts' info\n";
    for(auto &phone: phone_book)
        cout << phone << endl;
     
    cout << "\ntest whether the same contact\n";
    cout << boolalpha << (phone_book.at(0) == phone_book.at(1)) << endl;
}
 
int main() {
    test();
}

hpp

#pragma once
 
#include <iostream>
#include <string>
 
using namespace std;
using std::cin;
using std::cout;
using std::endl;
using std::string;
 
class Person
{
public:
    Person(string n = " ", string t = " ", string e = " ") : name{n}, telephone{t}, email{e} {}
    Person(const Person &p) : name{p.name}, telephone{p.telephone}, email{p.email} {}
    ~Person() = default;
    void update_telephone();
    void update_email();
 
    friend std::ostream &operator<<(std::ostream &out, Person &p);
    friend std::istream &operator>>(std::istream &in, Person &p);
    friend bool operator==(Person &p1, Person &p2);
 
private:
    string name,telephone,email;
};
 
void Person::update_telephone()
{
    cout << "Enter the telephone number: ";
    cin.clear();
    string new_telephone;
    cin>>new_telephone;
    telephone = new_telephone;
    cout<<"telephone number has been updated"<< endl;
}
 
void Person::update_email()
{
    cout << "Enter the email address: ";
    string new_email;
    cin.clear();
    cin >> new_email;
    cout << "email address has been updated..." << endl;
 
    email = new_email;
}