C++: Prática: Sistema de Agenda

Contact
  - name, phone, email

AddressBook
  - vector<Contact> contacts
  - add, remove, update, find, display
  - save, load

#include <iostream>
#include <string>
#include <fstream>

class Contact {
private:
	std::string name;
	std::string phone;
	std::string email;

public:
	Contact() = default;
	Contact(const std::string& name, const std::string& phone, const std::string& email)
	: name(name), phone(phone), email(email) {}
	
	// Getter
	std::string getName() const { return name; }
	std::string getPhone() const { return phone; }
	std::string getEmail() const { return email; }
	
	// Setter
	void setName(const std::string& n) { name = n; }
	void setPhone(const std::string& p) { phone = p; }
	void setEmail(const std::string& e) { email = e; }
	
	// Exibir
	void display() const {
		std::cout << "Name: " << name << std::endl;
		std::cout << "Phone: " << phone << std::endl;
		std::cout << "Email: " << email << std::endl;
		std::cout << "-------------------" << std::endl;
	}
	
	// Serializar (salvar em arquivo)
	void save(std::ofstream& file) const {
		file << name << "," << phone << "," << email << std::endl;
	}
	
	// Desserializar (carregar de arquivo)
	static Contact load(std::ifstream& file) {
		Contact c;
		std::getline(file, c.name, ',');
		std::getline(file, c.phone, ',');
		std::getline(file, c.email);
		return c;
	}
};

#include <vector>
#include <algorithm>

class AddressBook {
private:
	std::vector<Contact> contacts;

public:
	// Adicionar contato
	void addContact(const Contact& c) {
		contacts.push_back(c);
		std::cout << "Added successfully!" << std::endl;
	}
	
	// Buscar contato (por nome)
	Contact* findByName(const std::string& name) {
		for (auto& c : contacts) {
			if (c.getName() == name) {
				return &c;
			}
		}
		return nullptr;
	}
	
	// Excluir contato (por nome)
	bool removeByName(const std::string& name) {
		auto it = std::remove_if(contacts.begin(), contacts.end(),
			[&name](const Contact& c) {
				return c.getName() == name;
			});
		
		if (it != contacts.end()) {
			contacts.erase(it, contacts.end());
			std::cout << "Deleted successfully!" << std::endl;
			return true;
		}
		
		std::cout << "Contact not found: " << name << std::endl;
		return false;
	}
	
	// Exibir todos os contatos
	void displayAll() const {
		if (contacts.empty()) {
			std::cout << "Address book is empty" << std::endl;
			return;
		}
		
		for (const auto& c : contacts) {
			c.display();
		}
	}
	
	// Salvar em arquivo
	void saveToFile(const std::string& filename) const {
		std::ofstream file(filename);
		if (!file) {
			std::cerr << "Cannot open file" << std::endl;
			return;
		}
		
		for (const auto& c : contacts) {
			c.save(file);
		}
		
		file.close();
		std::cout << "Saved successfully!" << std::endl;
	}
	
	// Carregar de arquivo
	void loadFromFile(const std::string& filename) {
		std::ifstream file(filename);
		if (!file) {
			std::cerr << "Cannot open file" << std::endl;
			return;
		}
		
		contacts.clear(); // Limpar dados existentes
		
		std::string line;
		while (file.peek() != EOF) {
			contacts.push_back(Contact::load(file));
		}
		
		file.close();
		std::cout << "Loaded successfully!" << std::endl;
	}
};

Added successfully!
Deleted successfully!
Contact not found:
Address book is empty
Saved successfully!
Loaded successfully!

void showMenu() {
### ▶ Exemplo 2: Prática Básica de Programação (Dificuldade ⭐)

	std::cout << "\n===== Address Book Management System =====" << std::endl;
	std::cout << "1. Add contact" << std::endl;
	std::cout << "2. Delete contact" << std::endl;
	std::cout << "3. Find contact" << std::endl;
	std::cout << "4. Display all contacts" << std::endl;
	std::cout << "5. Save" << std::endl;
	std::cout << "6. Load" << std::endl;
	std::cout << "0. Exit" << std::endl;
	std::cout << "==========================================" << std::endl;
	std::cout << "Choose: ";
}

int main() {
	AddressBook book;
	int choice;
	
	do {
		showMenu();
		std::cin >> choice;
		
		switch (choice) {
		case 1: {
			std::string name, phone, email;
			std::cout << "Name: ";
			std::cin >> name;
			std::cout << "Phone: ";
			std::cin >> phone;
			std::cout << "Email: ";
			std::cin >> email;
			book.addContact(Contact(name, phone, email));
			break;
		}
		case 2: {
			std::string name;
			std::cout << "Name: ";
			std::cin >> name;
			book.removeByName(name);
			break;
		}
		case 3: {
			std::string name;
			std::cout << "Name: ";
			std::cin >> name;
			Contact* c = book.findByName(name);
			if (c) {
				c->display();
			} else {
				std::cout << "Not found" << std::endl;
			}
			break;
		}
		case 4:
			book.displayAll();
			break;
		case 5: {
			book.saveToFile("contacts.txt");
			break;
		}
		case 6: {
			book.loadFromFile("contacts.txt");
			break;
		}
		case 0:
			std::cout << "Goodbye!" << std::endl;
			break;
		default:
			std::cout << "Invalid choice" << std::endl;
		}
	} while (choice != 0);
	
	return 0;
}

#include <iostream>
#include <string>

struct Contact {
    std::string name;
    std::string phone;
    std::string email;

    void display() const {
        std::cout << "Name: " << name << std::endl;
        std::cout << "Phone: " << phone << std::endl;
        std::cout << "Email: " << email << std::endl;
    }
};

int main() {
    Contact c1 = {"Zhang San", "13800138000", "zhangsan@example.com"};
    Contact c2 = {"Li Si", "13900139000", "lisi@example.com"};

    c1.display();
    std::cout << "---" << std::endl;
    c2.display();

    return 0;
}

Name:
Phone:
Email:
---