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Module 00 Solutions

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Exercise 00: Megaphone

Section titled “Exercise 00: Megaphone”

A simple program to convert input to uppercase.

megaphone.cpp
#include <iostream>
#include <cctype>


int main(int argc, char **argv)
{
    // No arguments: print feedback noise
    if (argc == 1)
    {
        std::cout << "* LOUD AND UNBEARABLE FEEDBACK NOISE *" << std::endl;
        return 0;
    }


    // Convert each argument to uppercase
    for (int i = 1; i < argc; i++)
    {
        for (int j = 0; argv[i][j]; j++)
        {
            std::cout << (char)toupper(argv[i][j]);
        }
    }
    std::cout << std::endl;


    return 0;
}

Key Points:

  • Use std::cout instead of printf
  • toupper() returns int, cast to char
  • No spaces between arguments
  • Handle the no-argument case

Exercise 01: PhoneBook

Section titled “Exercise 01: PhoneBook”

A simple phonebook with ADD, SEARCH, and EXIT commands.

Contact.hpp

Section titled “Contact.hpp”
Contact.hpp
#ifndef CONTACT_HPP
#define CONTACT_HPP


#include <string>


class Contact {
private:
    std::string _firstName;
    std::string _lastName;
    std::string _nickname;
    std::string _phoneNumber;
    std::string _darkestSecret;
    bool        _isEmpty;


public:
    Contact();
    ~Contact();


    void        setFirstName(const std::string& firstName);
    void        setLastName(const std::string& lastName);
    void        setNickname(const std::string& nickname);
    void        setPhoneNumber(const std::string& phoneNumber);
    void        setDarkestSecret(const std::string& secret);
    void        setIsEmpty(bool isEmpty);


    std::string getFirstName() const;
    std::string getLastName() const;
    std::string getNickname() const;
    std::string getPhoneNumber() const;
    std::string getDarkestSecret() const;
    bool        isEmpty() const;
};


#endif

PhoneBook.hpp

Section titled “PhoneBook.hpp”
PhoneBook.hpp
#ifndef PHONEBOOK_HPP
#define PHONEBOOK_HPP


#include "Contact.hpp"
#include <string>


class PhoneBook {
private:
    Contact     _contacts[8];
    int         _currentIndex;
    int         _totalContacts;


    std::string _truncate(const std::string& str) const;
    void        _displayContactRow(int index) const;
    std::string _getInput(const std::string& prompt) const;


public:
    PhoneBook();
    ~PhoneBook();


    void        addContact();
    void        searchContacts() const;
};


#endif

Contact.cpp

Section titled “Contact.cpp”
Contact.cpp
#include "Contact.hpp"


Contact::Contact() : _isEmpty(true) {}


Contact::~Contact() {}


void Contact::setFirstName(const std::string& firstName) {
    _firstName = firstName;
}


void Contact::setLastName(const std::string& lastName) {
    _lastName = lastName;
}


void Contact::setNickname(const std::string& nickname) {
    _nickname = nickname;
}


void Contact::setPhoneNumber(const std::string& phoneNumber) {
    _phoneNumber = phoneNumber;
}


void Contact::setDarkestSecret(const std::string& secret) {
    _darkestSecret = secret;
}


void Contact::setIsEmpty(bool isEmpty) {
    _isEmpty = isEmpty;
}


std::string Contact::getFirstName() const { return _firstName; }
std::string Contact::getLastName() const { return _lastName; }
std::string Contact::getNickname() const { return _nickname; }
std::string Contact::getPhoneNumber() const { return _phoneNumber; }
std::string Contact::getDarkestSecret() const { return _darkestSecret; }
bool Contact::isEmpty() const { return _isEmpty; }

PhoneBook.cpp

Section titled “PhoneBook.cpp”
PhoneBook.cpp
#include "PhoneBook.hpp"
#include <iostream>
#include <iomanip>
#include <cstdlib>


PhoneBook::PhoneBook() : _currentIndex(0), _totalContacts(0) {}


PhoneBook::~PhoneBook() {}


std::string PhoneBook::_truncate(const std::string& str) const {
    if (str.length() > 10)
        return str.substr(0, 9) + ".";
    return str;
}


void PhoneBook::_displayContactRow(int index) const {
    std::cout << std::setw(10) << std::right << index << "|";
    std::cout << std::setw(10) << std::right << _truncate(_contacts[index].getFirstName()) << "|";
    std::cout << std::setw(10) << std::right << _truncate(_contacts[index].getLastName()) << "|";
    std::cout << std::setw(10) << std::right << _truncate(_contacts[index].getNickname()) << std::endl;
}


std::string PhoneBook::_getInput(const std::string& prompt) const {
    std::string input;


    while (true) {
        std::cout << prompt;
        if (!std::getline(std::cin, input)) {
            std::cout << std::endl;
            std::exit(0);
        }
        if (!input.empty())
            break;
        std::cout << "Field cannot be empty. Please try again." << std::endl;
    }
    return input;
}


void PhoneBook::addContact() {
    Contact newContact;


    newContact.setFirstName(_getInput("Enter first name: "));
    newContact.setLastName(_getInput("Enter last name: "));
    newContact.setNickname(_getInput("Enter nickname: "));
    newContact.setPhoneNumber(_getInput("Enter phone number: "));
    newContact.setDarkestSecret(_getInput("Enter darkest secret: "));
    newContact.setIsEmpty(false);


    _contacts[_currentIndex] = newContact;
    _currentIndex = (_currentIndex + 1) % 8;  // Circular buffer
    if (_totalContacts < 8)
        _totalContacts++;


    std::cout << "Contact added successfully!" << std::endl;
}


void PhoneBook::searchContacts() const {
    if (_totalContacts == 0) {
        std::cout << "PhoneBook is empty." << std::endl;
        return;
    }


    // Display header
    std::cout << std::setw(10) << "Index" << "|";
    std::cout << std::setw(10) << "First Name" << "|";
    std::cout << std::setw(10) << "Last Name" << "|";
    std::cout << std::setw(10) << "Nickname" << std::endl;
    std::cout << std::string(44, '-') << std::endl;


    // Display all contacts
    for (int i = 0; i < _totalContacts; i++)
        _displayContactRow(i);


    // Get index from user
    std::cout << "Enter index to view details: ";
    std::string indexStr;
    if (!std::getline(std::cin, indexStr)) {
        std::cout << std::endl;
        return;
    }


    // Validate index
    if (indexStr.length() != 1 || indexStr[0] < '0' || indexStr[0] > '7') {
        std::cout << "Invalid index." << std::endl;
        return;
    }


    int index = indexStr[0] - '0';
    if (index >= _totalContacts) {
        std::cout << "Invalid index." << std::endl;
        return;
    }


    // Display full contact details
    std::cout << "First Name: " << _contacts[index].getFirstName() << std::endl;
    std::cout << "Last Name: " << _contacts[index].getLastName() << std::endl;
    std::cout << "Nickname: " << _contacts[index].getNickname() << std::endl;
    std::cout << "Phone Number: " << _contacts[index].getPhoneNumber() << std::endl;
    std::cout << "Darkest Secret: " << _contacts[index].getDarkestSecret() << std::endl;
}

Key Points:

  • Fixed array of 8 contacts (no dynamic allocation)
  • Circular buffer: oldest contact replaced when full
  • All attributes private with getters/setters
  • Truncate strings > 10 chars with .
  • Use std::setw(10) and std::right for formatting
  • Handle EOF (Ctrl+D) gracefully
  • Reject empty fields

Exercise 02: The Job Of Your Dreams

Section titled “Exercise 02: The Job Of Your Dreams”

Reconstruct Account.cpp from the provided Account.hpp and log file. Static members track global state across all accounts.

Account.cpp

Section titled “Account.cpp”
Account.cpp
#include "Account.hpp"
#include <iostream>
#include <iomanip>
#include <ctime>


// Initialize static members
int Account::_nbAccounts = 0;
int Account::_totalAmount = 0;
int Account::_totalNbDeposits = 0;
int Account::_totalNbWithdrawals = 0;


// Static getters
int Account::getNbAccounts() { return _nbAccounts; }
int Account::getTotalAmount() { return _totalAmount; }
int Account::getNbDeposits() { return _totalNbDeposits; }
int Account::getNbWithdrawals() { return _totalNbWithdrawals; }


// Display timestamp: [YYYYMMDD_HHMMSS]
void Account::_displayTimestamp() {
    std::time_t now = std::time(NULL);
    std::tm* local = std::localtime(&now);


    std::cout << "["
              << (local->tm_year + 1900)
              << std::setfill('0') << std::setw(2) << (local->tm_mon + 1)
              << std::setfill('0') << std::setw(2) << local->tm_mday
              << "_"
              << std::setfill('0') << std::setw(2) << local->tm_hour
              << std::setfill('0') << std::setw(2) << local->tm_min
              << std::setfill('0') << std::setw(2) << local->tm_sec
              << "] ";
}


// Display all accounts info
void Account::displayAccountsInfos() {
    _displayTimestamp();
    std::cout << "accounts:" << _nbAccounts
              << ";total:" << _totalAmount
              << ";deposits:" << _totalNbDeposits
              << ";withdrawals:" << _totalNbWithdrawals << std::endl;
}


// Constructor with initial deposit
Account::Account(int initial_deposit)
    : _accountIndex(_nbAccounts),
      _amount(initial_deposit),
      _nbDeposits(0),
      _nbWithdrawals(0) {
    _nbAccounts++;
    _totalAmount += initial_deposit;


    _displayTimestamp();
    std::cout << "index:" << _accountIndex
              << ";amount:" << _amount
              << ";created" << std::endl;
}


// Destructor
Account::~Account() {
    _displayTimestamp();
    std::cout << "index:" << _accountIndex
              << ";amount:" << _amount
              << ";closed" << std::endl;
}


// Make a deposit
void Account::makeDeposit(int deposit) {
    _displayTimestamp();
    std::cout << "index:" << _accountIndex
              << ";p_amount:" << _amount
              << ";deposit:" << deposit;


    _amount += deposit;
    _nbDeposits++;
    _totalAmount += deposit;
    _totalNbDeposits++;


    std::cout << ";amount:" << _amount
              << ";nb_deposits:" << _nbDeposits << std::endl;
}


// Make a withdrawal (returns false if insufficient funds)
bool Account::makeWithdrawal(int withdrawal) {
    _displayTimestamp();
    std::cout << "index:" << _accountIndex
              << ";p_amount:" << _amount
              << ";withdrawal:";


    if (withdrawal > _amount) {
        std::cout << "refused" << std::endl;
        return false;
    }


    _amount -= withdrawal;
    _nbWithdrawals++;
    _totalAmount -= withdrawal;
    _totalNbWithdrawals++;


    std::cout << withdrawal
              << ";amount:" << _amount
              << ";nb_withdrawals:" << _nbWithdrawals << std::endl;
    return true;
}


// Check current amount
int Account::checkAmount() const {
    return _amount;
}


// Display individual account status
void Account::displayStatus() const {
    _displayTimestamp();
    std::cout << "index:" << _accountIndex
              << ";amount:" << _amount
              << ";deposits:" << _nbDeposits
              << ";withdrawals:" << _nbWithdrawals << std::endl;
}

Key Points:

  • Static members must be initialized outside the class (in .cpp file)
  • _displayTimestamp() uses <ctime> functions: time(), localtime()
  • Use std::setfill('0') and std::setw(2) for zero-padded numbers
  • Constructor increments _nbAccounts and adds to _totalAmount
  • makeWithdrawal() returns false and prints “refused” if insufficient funds
  • Output format must match the log file exactly (semicolon-separated key:value pairs)