feat(Week07): Add solutions

17 files changed, 1539 insertions, 0 deletions

diff --git a/Week07/Exercise01/BankClerk.cpp b/Week07/Exercise01/BankClerk.cpp
new file mode 100644
index 0000000..697894b
--- /dev/null
+++ b/Week07/Exercise01/BankClerk.cpp
@@ -0,0 +1,21 @@
+#include "BankClerk.h"
+
+BankClerk::BankClerk(unsigned clerkNumber) {
+	this->clerkNumber = clerkNumber;
+	this->staticPassword = "password";
+}
+
+BankClerk::BankClerk() : clerkNumber(0), staticPassword()
+{ }
+
+unsigned BankClerk::GetClerkNumber() const {
+	return clerkNumber;
+}
+
+void BankClerk::SetPassword(const String& newPassword) {
+	staticPassword = newPassword;
+}
+
+bool BankClerk::Login(unsigned clerkNumber, unsigned dynamicPassword, const String& staticPassword) {
+	return (clerkNumber * dynamicPassword) % 8581 == 0 && this->staticPassword.EqualTo(staticPassword);
+}
diff --git a/Week07/Exercise01/BankClerk.h b/Week07/Exercise01/BankClerk.h
new file mode 100644
index 0000000..5692ef8
--- /dev/null
+++ b/Week07/Exercise01/BankClerk.h
@@ -0,0 +1,23 @@
+#ifndef _BANKCLERK
+#define _BANKCLERK
+
+#include "String.h"
+
+class BankClerk {
+	unsigned clerkNumber;
+	String staticPassword;
+
+public:
+	BankClerk(unsigned clerkNumber);
+	// Ако направим поне един конструктор, то конструктора по подразбиране
+	// спира да се създава автоматично
+	BankClerk();
+
+	unsigned GetClerkNumber() const;
+
+	void SetPassword(const String& newPassword);
+
+	bool Login(unsigned clerkNumber, unsigned dynamicPassword, const String& staticPassword);
+};
+
+#endif /* _BANKCLERK */
diff --git a/Week07/Exercise01/Book.cpp b/Week07/Exercise01/Book.cpp
new file mode 100644
index 0000000..d48e090
--- /dev/null
+++ b/Week07/Exercise01/Book.cpp
@@ -0,0 +1,96 @@
+#include "Book.h"
+#include <iostream>
+#include <fstream>
+
+void Book::SetTitle(const String& newTitle) {
+	title = newTitle;
+}
+
+const String& Book::GetTitle() const {
+	return title;
+}
+
+void Book::SetAuthor(const String& newAuthor) {
+	author = newAuthor;
+}
+
+const String& Book::GetAuthor() const {
+	return author;
+}
+
+void Book::SetYear(short newYear) {
+	year = newYear;
+}
+
+short Book::GetYear() const {
+	return year;
+}
+
+void Book::SetText(const String& newText) {
+	text = newText;
+}
+
+const String& Book::GetText() const {
+	return text;
+}
+
+void Book::SetPrice(double newPrice) {
+	price = newPrice;
+}
+
+double Book::GetPrice() const {
+	return price;
+}
+
+void Book::SetAvailableForPurchase(bool isAvailableForPurchase) {
+	availableForPurchase = isAvailableForPurchase;
+}
+
+bool Book::GetAvailableForPurchase() const {
+	return availableForPurchase;
+}
+
+void Book::PrintBookInfo() const {
+	std::cout << GetTitle().GetStr() << ", "
+		<< GetAuthor().GetStr() << ' '
+		<< GetYear() << std::endl;
+}
+
+bool Book::Export(const String& fileName) {
+	std::ofstream exportFile(fileName.GetStr(), std::ios::binary);
+
+	if (!exportFile.is_open()) {
+		std::cout << "Couldn't export book to file!" << std::endl;
+	}
+	else {
+		exportFile.write(title.GetStr(), title.GetLength() + 1);
+		exportFile.write(author.GetStr(), author.GetLength() + 1);
+		exportFile.write((const char*)&year, sizeof(year));
+		exportFile.write(text.GetStr(), text.GetLength() + 1);
+	}
+
+	return exportFile.is_open();
+}
+
+void readNullTerminated(String& readInto, std::ifstream& file) {
+	readInto.Clear();
+	for (char buffer = file.get(); buffer != '\0' && !file.eof(); buffer = file.get()) {
+		readInto.AppendChar(buffer);
+	}
+}
+
+bool Book::Import(const String& fileName) {
+	std::ifstream importFile(fileName.GetStr(), std::ios::binary);
+
+	if (!importFile.is_open()) {
+		std::cout << "Couldn't import book to file!" << std::endl;
+	}
+	else {
+		readNullTerminated(title, importFile);
+		readNullTerminated(author, importFile);
+		importFile.read((char*)&year, sizeof(year));
+		readNullTerminated(text, importFile);
+	}
+
+	return importFile.is_open();
+}
diff --git a/Week07/Exercise01/Book.h b/Week07/Exercise01/Book.h
new file mode 100644
index 0000000..eaddaea
--- /dev/null
+++ b/Week07/Exercise01/Book.h
@@ -0,0 +1,39 @@
+#ifndef _BOOK
+#define _BOOK
+
+#include "String.h"
+
+class Book {
+	String title;
+	String author;
+	short year;
+	String text;
+	double price;
+	bool availableForPurchase;
+
+public:
+	void SetTitle(const String& newTitle);
+	const String& GetTitle() const;
+
+	void SetAuthor(const String& newAuthor);
+	const String& GetAuthor() const;
+
+	void SetYear(short newYear);
+	short GetYear() const;
+
+	void SetText(const String& newText);
+	const String& GetText() const;
+
+	void SetPrice(double newPrice);
+	double GetPrice() const;
+
+	void SetAvailableForPurchase(bool isAvailableForPurchase);
+	bool GetAvailableForPurchase() const;
+
+	void PrintBookInfo() const;
+
+	bool Export(const String& fileName);
+	bool Import(const String& fileName);
+};
+
+#endif /* _BOOK */
diff --git a/Week07/Exercise01/Librarian.cpp b/Week07/Exercise01/Librarian.cpp
new file mode 100644
index 0000000..0e6179d
--- /dev/null
+++ b/Week07/Exercise01/Librarian.cpp
@@ -0,0 +1,21 @@
+#include "Librarian.h"
+
+Librarian::Librarian(unsigned librarianNumber) {
+	this->librarianNumber = librarianNumber;
+	this->password = "password";
+}
+
+Librarian::Librarian() : librarianNumber(0), password()
+{ }
+
+unsigned Librarian::GetLibrarianNumber() const {
+	return librarianNumber;
+}
+
+void Librarian::SetPassword(const String& newPassword) {
+	this->password = newPassword;
+}
+
+bool Librarian::Login(unsigned librarianNumber, const String& password) {
+	return this->librarianNumber == librarianNumber && this->password.EqualTo(password);
+}
diff --git a/Week07/Exercise01/Librarian.h b/Week07/Exercise01/Librarian.h
new file mode 100644
index 0000000..839a258
--- /dev/null
+++ b/Week07/Exercise01/Librarian.h
@@ -0,0 +1,23 @@
+#ifndef _LIBRARIAN
+#define _LIBRARIAN
+
+#include "String.h"
+
+class Librarian {
+	unsigned librarianNumber;
+	String password;
+
+public:
+	Librarian(unsigned librarianNumber);
+	// Ако направим поне един конструктор, то конструктора по подразбиране
+	// спира да се създава автоматично
+	Librarian();
+
+	unsigned GetLibrarianNumber() const;
+
+	void SetPassword(const String& newPassword);
+
+	bool Login(unsigned librarianNumber, const String& password);
+};
+
+#endif /* _LIBRARIAN */
diff --git a/Week07/Exercise01/LibraryBanking.cpp b/Week07/Exercise01/LibraryBanking.cpp
new file mode 100644
index 0000000..66e0959
--- /dev/null
+++ b/Week07/Exercise01/LibraryBanking.cpp
@@ -0,0 +1,159 @@
+#include "LibraryBanking.h"
+#include "Transaction.h"
+#include <fstream>
+#include <iostream>
+
+void LibraryBanking::free() {
+	delete[] clerks;
+	delete[] transactions;
+}
+
+void LibraryBanking::copyFrom(const LibraryBanking& other) {
+	clerksAlloc = other.clerksAlloc;
+	clerksCount = other.clerksCount;
+	clerks = new BankClerk[clerksAlloc];
+	for (unsigned i = 0; i < clerksCount; ++i)
+		clerks[i] = other.clerks[i];
+
+	transactionsAlloc = other.transactionsAlloc;
+	transactionsCount = other.transactionsCount;
+	transactions = new Transaction[transactionsAlloc];
+	for (unsigned i = 0; i < transactionsCount; ++i)
+		transactions[i] = other.transactions[i];
+}
+
+void LibraryBanking::resizeClerks() {
+	clerksAlloc = clerksAlloc == 0 ? 8 : clerksAlloc * 2;
+	BankClerk* newClerks = new BankClerk[clerksAlloc];
+
+	for (unsigned i = 0; i < clerksCount; ++i)
+		newClerks[i] = clerks[i];
+
+	delete[] clerks;
+	clerks = newClerks;
+}
+
+void LibraryBanking::resizeTransactions() {
+	transactionsAlloc = transactionsAlloc == 0 ? 8 : transactionsAlloc * 2;
+	Transaction* newTransactions = new Transaction[transactionsAlloc];
+
+	for (unsigned i = 0; i < transactionsCount; ++i)
+		newTransactions[i] = transactions[i];
+
+	delete[] transactions;
+	transactions = newTransactions;
+}
+
+LibraryBanking::LibraryBanking() : clerks(nullptr), clerksCount(0), clerksAlloc(0), transactions(nullptr), transactionsCount(0), transactionsAlloc(0)
+{ }
+
+LibraryBanking::~LibraryBanking() {
+	free();
+}
+
+LibraryBanking::LibraryBanking(const LibraryBanking& other) {
+	copyFrom(other);
+}
+
+LibraryBanking& LibraryBanking::operator=(const LibraryBanking& other) {
+	if (this != &other) {
+		free();
+		copyFrom(other);
+	}
+	return *this;
+}
+
+LibraryBanking::LibraryBanking(LibraryBanking&& other) {
+	clerks = other.clerks;
+	clerksCount = other.clerksCount;
+	clerksAlloc = other.clerksAlloc;
+
+	transactions = other.transactions;
+	transactionsCount = other.transactionsCount;
+	transactionsAlloc = other.transactionsAlloc;
+
+	other.clerks = nullptr;
+	other.clerksCount = other.clerksAlloc = 0;
+
+	other.transactions = nullptr;
+	other.transactionsCount = other.transactionsAlloc = 0;
+}
+
+LibraryBanking& LibraryBanking::operator=(LibraryBanking&& other) {
+	if (this != &other) {
+		free();
+
+		clerks = other.clerks;
+		clerksCount = other.clerksCount;
+		clerksAlloc = other.clerksAlloc;
+
+		transactions = other.transactions;
+		transactionsCount = other.transactionsCount;
+		transactionsAlloc = other.transactionsAlloc;
+
+		other.clerks = nullptr;
+		other.clerksCount = other.clerksAlloc = 0;
+
+		other.transactions = nullptr;
+		other.transactionsCount = other.transactionsAlloc = 0;
+	}
+	return *this;
+}
+
+void LibraryBanking::RegisterClerk(const BankClerk& clerk) {
+	if (clerksCount >= clerksAlloc)
+		resizeClerks();
+	clerks[clerksCount++] = clerk;
+}
+
+BankClerk* LibraryBanking::LoginClerk(unsigned clerkNumber, unsigned dynamicPassword, const String& staticPassword) {
+	for (unsigned i = 0; i < clerksCount; ++i) {
+		if (clerks[i].Login(clerkNumber, dynamicPassword, staticPassword))
+			// "clerks + i" е същото като "&clerks[i]"
+			return clerks + i;
+	}
+	return nullptr;
+}
+
+void LibraryBanking::ListPendingTransactions() {
+	for (unsigned i = 0; i < transactionsCount; ++i) {
+		if (transactions[i].GetStatus() == STATUS_PENDING) {
+			std::cout << '[' << i << "] ";
+			transactions[i].PrintTransactionInfo();
+		}
+	}
+}
+
+Transaction* LibraryBanking::GetTransaction(unsigned index) {
+	if (index >= transactionsCount)
+		return nullptr;
+	// "transactions + index" е същото като "&transactions[index]"
+	return transactions + index;
+}
+
+const Transaction* LibraryBanking::RegisterTransaction(const Transaction& transaction) {
+	if (transactionsCount >= transactionsAlloc)
+		resizeTransactions();
+	transactions[transactionsCount] = transaction;
+
+	if (transaction.GetSum() == 0.0)
+		transactions[transactionsCount].SetStatus(0, STATUS_ACCEPTED);
+
+	return transactions + transactionsCount++;
+}
+
+void LibraryBanking::ExportNonPendingTransactions(const String& fileName) {
+	std::ofstream exportFile(fileName.GetStr(), std::ios::trunc);
+
+	if (!exportFile.is_open()) {
+		std::cout << "Couldn't open file!" << std::endl;
+	}
+	else {
+		for (unsigned i = 0; i < transactionsCount; ++i) {
+			if (transactions[i].GetStatus() != STATUS_PENDING) {
+				exportFile << i << ",";
+				transactions[i].Export(exportFile);
+			}
+		}
+	}
+}
diff --git a/Week07/Exercise01/LibraryBanking.h b/Week07/Exercise01/LibraryBanking.h
new file mode 100644
index 0000000..08e9d9d
--- /dev/null
+++ b/Week07/Exercise01/LibraryBanking.h
@@ -0,0 +1,40 @@
+#ifndef _LIBRARY_BANKING
+#define _LIBRARY_BANKING
+
+#include "BankClerk.h"
+#include "Transaction.h"
+
+class LibraryBanking {
+	BankClerk* clerks;
+	unsigned clerksCount;
+	unsigned clerksAlloc;
+
+	Transaction* transactions;
+	unsigned transactionsCount;
+	unsigned transactionsAlloc;
+
+	void free();
+	void copyFrom(const LibraryBanking& other);
+
+	void resizeClerks();
+	void resizeTransactions();
+
+public:
+	LibraryBanking();
+	~LibraryBanking();
+	LibraryBanking(const LibraryBanking& other);
+	LibraryBanking& operator=(const LibraryBanking& other);
+	LibraryBanking(LibraryBanking&& other);
+	LibraryBanking& operator=(LibraryBanking&& other);
+
+	void RegisterClerk(const BankClerk& clerk);
+	BankClerk* LoginClerk(unsigned clerkNumber, unsigned dynamicPassword, const String& staticPassword);
+
+	void ListPendingTransactions();
+	Transaction* GetTransaction(unsigned index);
+	const Transaction* RegisterTransaction(const Transaction& transaction);
+
+	void ExportNonPendingTransactions(const String& fileName);
+};
+
+#endif /* _LIBRARY_BANKING */
diff --git a/Week07/Exercise01/OnlineLibrary.cpp b/Week07/Exercise01/OnlineLibrary.cpp
new file mode 100644
index 0000000..495ee95
--- /dev/null
+++ b/Week07/Exercise01/OnlineLibrary.cpp
@@ -0,0 +1,264 @@
+#include "OnlineLibrary.h"
+#include <iostream>
+
+void OnlineLibrary::free() {
+	delete[] books;
+	delete[] users;
+	delete[] librarians;
+	delete[] connections;
+}
+
+void OnlineLibrary::copyFrom(const OnlineLibrary& other) {
+	booksCount = other.booksCount;
+	booksAlloc = other.booksAlloc;
+	books = new Book[booksAlloc];
+	for (unsigned i = 0; i < booksCount; ++i)
+		books[i] = other.books[i];
+
+	usersCount = other.usersCount;
+	usersAlloc = other.usersAlloc;
+	users = new User[usersAlloc];
+	for (unsigned i = 0; i < usersCount; ++i)
+		users[i] = other.users[i];
+
+	librariansCount = other.librariansCount;
+	librariansAlloc = other.librariansAlloc;
+	librarians = new Librarian[librariansAlloc];
+	for (unsigned i = 0; i < librariansCount; ++i)
+		librarians[i] = other.librarians[i];
+
+	connectionsCount = other.connectionsCount;
+	connectionsAlloc = other.connectionsAlloc;
+	connections = new TransactionConnection[connectionsAlloc];
+	for (unsigned i = 0; i < connectionsCount; ++i)
+		connections[i] = other.connections[i];
+}
+
+void OnlineLibrary::resizeBooks() {
+	booksAlloc = booksAlloc == 0 ? 8 : booksAlloc * 2;
+	Book* booksLarger = new Book[booksAlloc];
+
+	for (unsigned i = 0; i < booksCount; ++i)
+		booksLarger[i] = books[i];
+
+	delete[] books;
+	books = booksLarger;
+}
+
+void OnlineLibrary::resizeUsers() {
+	usersAlloc = usersAlloc == 0 ? 8 : usersAlloc * 2;
+	User* usersLarger = new User[usersAlloc];
+
+	for (unsigned i = 0; i < usersCount; ++i)
+		usersLarger[i] = users[i];
+
+	delete[] users;
+	users = usersLarger;
+}
+
+void OnlineLibrary::resizeLibrarians() {
+	librariansAlloc = librariansAlloc == 0 ? 8 : librariansAlloc * 2;
+	Librarian* librariansLarger = new Librarian[librariansAlloc];
+
+	for (unsigned i = 0; i < librariansCount; ++i)
+		librariansLarger[i] = librarians[i];
+
+	delete[] librarians;
+	librarians = librariansLarger;
+}
+
+void OnlineLibrary::resizeConnections() {
+	connectionsAlloc = connectionsAlloc == 0 ? 8 : connectionsAlloc * 2;
+	TransactionConnection* connectionsLarger = new TransactionConnection[connectionsAlloc];
+
+	for (unsigned i = 0; i < connectionsCount; ++i)
+		connectionsLarger[i] = connections[i];
+
+	delete[] connections;
+	connections = connectionsLarger;
+}
+
+OnlineLibrary::OnlineLibrary() {
+	books = nullptr;
+	booksCount = booksAlloc = 0;
+	users = nullptr;
+	usersCount = usersAlloc = 0;
+	librarians = nullptr;
+	librariansCount = librariansAlloc = 0;
+	connections = nullptr;
+	connectionsCount = connectionsAlloc = 0;
+}
+
+OnlineLibrary::~OnlineLibrary() {
+	free();
+}
+
+OnlineLibrary::OnlineLibrary(const OnlineLibrary& other) {
+	copyFrom(other);
+}
+
+OnlineLibrary& OnlineLibrary::operator=(const OnlineLibrary& other) {
+	if (this != &other) {
+		free();
+		copyFrom(other);
+	}
+	return *this;
+}
+
+OnlineLibrary::OnlineLibrary(OnlineLibrary&& other) {
+	books = other.books;
+	booksCount = other.booksCount;
+	booksAlloc = other.booksAlloc;
+
+	users = other.users;
+	usersCount = other.usersCount;
+	usersAlloc = other.usersAlloc;
+
+	librarians = other.librarians;
+	librariansCount = other.librariansCount;
+	librariansAlloc = other.librariansAlloc;
+
+	connections = other.connections;
+	connectionsCount = other.connectionsCount;
+	connectionsAlloc = other.connectionsAlloc;
+
+	other.books = nullptr;
+	other.booksCount = other.booksAlloc = 0;
+
+	other.users = nullptr;
+	other.usersCount = other.usersAlloc = 0;
+
+	other.librarians = nullptr;
+	other.librariansCount = other.librariansAlloc = 0;
+
+	other.connections = nullptr;
+	other.connectionsCount = other.connectionsAlloc = 0;
+}
+
+OnlineLibrary& OnlineLibrary::operator=(OnlineLibrary&& other) {
+	if (this != &other) {
+		free();
+
+		books = other.books;
+		booksCount = other.booksCount;
+		booksAlloc = other.booksAlloc;
+
+		users = other.users;
+		usersCount = other.usersCount;
+		usersAlloc = other.usersAlloc;
+
+		librarians = other.librarians;
+		librariansCount = other.librariansCount;
+		librariansAlloc = other.librariansAlloc;
+
+		connections = other.connections;
+		connectionsCount = other.connectionsCount;
+		connectionsAlloc = other.connectionsAlloc;
+
+		other.books = nullptr;
+		other.booksCount = other.booksAlloc = 0;
+
+		other.users = nullptr;
+		other.usersCount = other.usersAlloc = 0;
+
+		other.librarians = nullptr;
+		other.librariansCount = other.librariansAlloc = 0;
+
+		other.connections = nullptr;
+		other.connectionsCount = other.connectionsAlloc = 0;
+	}
+	return *this;
+}
+
+void OnlineLibrary::RegisterUser(const User& user) {
+	if (usersCount >= usersAlloc)
+		resizeUsers();
+	users[usersCount++] = user;
+}
+
+User* OnlineLibrary::LoginUser(const String& email, const String& password) {
+	for (unsigned i = 0; i < usersCount; ++i) {
+		if (users[i].Login(email, password))
+			// "users + i" е същото като "&users[i]"
+			return users + i;
+	}
+	return nullptr;
+}
+
+void OnlineLibrary::RegisterLibrarian(const Librarian& librarian) {
+	if (librariansCount >= librariansAlloc)
+		resizeLibrarians();
+	librarians[librariansCount++] = librarian;
+}
+
+Librarian* OnlineLibrary::LoginLibrarian(unsigned librarianNumber, const String& password) {
+	for (unsigned i = 0; i < librariansCount; ++i) {
+		if (librarians[i].Login(librarianNumber, password))
+			// "librarians + i" е същото като "&librarians[i]"
+			return librarians + i;
+	}
+	return nullptr;
+}
+
+void OnlineLibrary::ListBooks() const {
+	for (unsigned i = 0; i < booksCount; ++i) {
+		if (books[i].GetAvailableForPurchase()) {
+			std::cout << '[' << i << "] ";
+			books[i].PrintBookInfo();
+		}
+	}
+}
+
+Book* OnlineLibrary::GetBook(unsigned index) {
+	if (index >= booksCount)
+		return nullptr;
+	// "books + index" е същото като "&books[index]"
+	return books + index;
+}
+
+void OnlineLibrary::AddBook(const Book& book) {
+	if (booksCount >= booksAlloc)
+		resizeBooks();
+	books[booksCount++] = book;
+}
+
+void OnlineLibrary::PurchaseBook(const Book& book, const User& user, LibraryBanking& banking) {
+	if (connectionsCount >= connectionsAlloc)
+		resizeConnections();
+
+	TransactionConnection tc;
+	tc.user = &user;
+	tc.book = &book;
+	tc.transaction = banking.RegisterTransaction(Transaction(book.GetPrice(), user.GetBankCard()));
+
+	connections[connectionsCount++] = tc;
+}
+
+void OnlineLibrary::ListTransactions(const User& user) const {
+	for (unsigned i = 0; i < connectionsCount; ++i) {
+		if (connections[i].user == &user) {
+			std::cout << connections[i].book->GetTitle().GetStr() << ", "
+				<< connections[i].book->GetAuthor().GetStr() << " Price:"
+				<< connections[i].book->GetPrice() << " Card:"
+				<< connections[i].transaction->GetBankCard() << " Status:"
+				<< connections[i].transaction->GetStatusStr().GetStr() << std::endl;
+		}
+	}
+}
+
+void OnlineLibrary::ExportTransactions(const User& user, const String& fileName) const {
+	std::ofstream exportFile(fileName.GetStr(), std::ios::trunc);
+
+	if (!exportFile.is_open()) {
+		std::cout << "Couldn't open export file!" << std::endl;
+	}
+	else {
+		for (unsigned i = 0; i < connectionsCount; ++i) {
+			if (connections[i].user == &user) {
+				exportFile << i << ','
+					<< connections[i].book->GetTitle().GetStr() << ',';
+				connections[i].transaction->Export(exportFile);
+			}
+		}
+	}
+}
diff --git a/Week07/Exercise01/OnlineLibrary.h b/Week07/Exercise01/OnlineLibrary.h
new file mode 100644
index 0000000..4121af0
--- /dev/null
+++ b/Week07/Exercise01/OnlineLibrary.h
@@ -0,0 +1,65 @@
+#ifndef _ONLINE_LIBRARY
+#define _ONLINE_LIBRARY
+
+#include "Book.h"
+#include "LibraryBanking.h"
+#include "Transaction.h"
+#include "User.h"
+#include "Librarian.h"
+
+class OnlineLibrary {
+	Book* books;
+	unsigned booksCount;
+	unsigned booksAlloc;
+
+	User* users;
+	unsigned usersCount;
+	unsigned usersAlloc;
+
+	Librarian* librarians;
+	unsigned librariansCount;
+	unsigned librariansAlloc;
+
+	// В методи на OnlineLibrary, тази структура се казва "TransactionConnection"
+	// Извън методи на OnlineLibrary, тази структура се казва "OnlineLibrary::TransactionConnection"
+	struct TransactionConnection {
+		const User* user;
+		const Book* book;
+		const Transaction* transaction;
+	};
+	TransactionConnection* connections;
+	unsigned connectionsCount;
+	unsigned connectionsAlloc;
+
+	void free();
+	void copyFrom(const OnlineLibrary& other);
+
+	void resizeBooks();
+	void resizeUsers();
+	void resizeLibrarians();
+	void resizeConnections();
+
+public:
+	OnlineLibrary();
+	~OnlineLibrary();
+	OnlineLibrary(const OnlineLibrary& other);
+	OnlineLibrary& operator=(const OnlineLibrary& other);
+	OnlineLibrary(OnlineLibrary&& other);
+	OnlineLibrary& operator=(OnlineLibrary&& other);
+
+	void RegisterUser(const User& user);
+	User* LoginUser(const String& email, const String& password);
+
+	void RegisterLibrarian(const Librarian& librarian);
+	Librarian* LoginLibrarian(unsigned librarianNumber, const String& password);
+
+	void ListBooks() const;
+	Book* GetBook(unsigned index);
+	void AddBook(const Book& book);
+	void PurchaseBook(const Book& book, const User& user, LibraryBanking& banking);
+
+	void ListTransactions(const User& user) const;
+	void ExportTransactions(const User& user, const String& fileName) const;
+};
+
+#endif /* _ONLINE_LIBRARY */
diff --git a/Week07/Exercise01/String.cpp b/Week07/Exercise01/String.cpp
new file mode 100644
index 0000000..8272658
--- /dev/null
+++ b/Week07/Exercise01/String.cpp
@@ -0,0 +1,98 @@
+#include "String.h"
+#include <cstring>
+
+void String::free() {
+	delete[] str;
+}
+
+void String::copyFrom(const String& other) {
+	length = other.length;
+
+	// Не забравяме за терминиращата нула
+	str = new char[length + 1];
+	strncpy(str, other.str, length + 1);
+}
+
+void String::resize() {
+	allocated = allocated == 0 ? 8 : allocated * 2;
+	char* strLarger = new char[allocated];
+
+	memcpy(strLarger, str, length);
+	strLarger[length] = '\0';
+
+	delete[] str;
+	str = strLarger;
+}
+
+String::String() {
+	str = nullptr;
+	allocated = length = 0;
+}
+
+String::~String() {
+	free();
+}
+
+String::String(const String& other) {
+	copyFrom(other);
+}
+
+String& String::operator=(const String& other) {
+	if (this != &other) {
+		free();
+		copyFrom(other);
+	}
+	return *this;
+}
+
+String::String(String&& other) {
+	str = other.str;
+	length = other.length;
+
+	other.str = nullptr;
+	other.length = 0;
+}
+
+String& String::operator=(String&& other) {
+	if (this != &other) {
+		free();
+
+		str = other.str;
+		length = other.length;
+
+		other.str = nullptr;
+		other.length = 0;
+	}
+	return *this;
+}
+
+String::String(const char* str) {
+	length = strlen(str);
+	this->str = new char[length + 1];
+	strncpy(this->str, str, length + 1);
+}
+
+void String::Clear() {
+	free();
+	str = nullptr;
+	length = allocated = 0;
+}
+
+void String::AppendChar(char c) {
+	if (length + 1 >= allocated)
+		resize();
+	str[length++] = c;
+	str[length] = '\0';
+}
+
+bool String::EqualTo(const String& other) const {
+	return strcmp(str, other.str) == 0;
+}
+
+const char* String::GetStr() const {
+	return str;
+}
+
+unsigned String::GetLength() const {
+	return length;
+}
diff --git a/Week07/Exercise01/String.h b/Week07/Exercise01/String.h
new file mode 100644
index 0000000..c9cc263
--- /dev/null
+++ b/Week07/Exercise01/String.h
@@ -0,0 +1,33 @@
+#ifndef _STRING
+#define _STRING
+
+class String {
+	char* str;
+	unsigned length;
+	unsigned allocated;
+
+	void free();
+	void copyFrom(const String& other);
+
+	void resize();
+
+public:
+	String();
+	~String();
+	String(const String& other);
+	String& operator=(const String& other);
+	String(String&& other);
+	String& operator=(String&& other);
+
+	String(const char* str);
+	void Clear();
+
+	void AppendChar(char c);
+
+	bool EqualTo(const String& other) const;
+
+	const char* GetStr() const;
+	unsigned GetLength() const;
+};
+
+#endif /* _STRING */
diff --git a/Week07/Exercise01/Transaction.cpp b/Week07/Exercise01/Transaction.cpp
new file mode 100644
index 0000000..8978c05
--- /dev/null
+++ b/Week07/Exercise01/Transaction.cpp
@@ -0,0 +1,56 @@
+#include "Transaction.h"
+#include <iostream>
+
+Transaction::Transaction(double sum, unsigned bankCard) {
+	this->clerkNumber = 0;
+	this->sum = sum;
+	this->bankCard = bankCard;
+	this->status = STATUS_PENDING;
+}
+
+Transaction::Transaction() : clerkNumber(0), sum(0), bankCard(0), status(0)
+{ }
+
+unsigned Transaction::GetClerkNumber() const {
+	return clerkNumber;
+}
+
+double Transaction::GetSum() const {
+	return sum;
+}
+
+unsigned Transaction::GetBankCard() const {
+	return bankCard;
+}
+
+unsigned Transaction::GetStatus() const {
+	return status;
+}
+
+String Transaction::GetStatusStr() const {
+	switch (status) {
+		case STATUS_PENDING: return "Pending";
+		case STATUS_ACCEPTED: return "Accepted";
+		case STATUS_REJECTED: return "Rejected";
+	}
+	return "";
+}
+
+void Transaction::SetStatus(unsigned clerk, unsigned status) {
+	this->clerkNumber = clerk;
+	this->status = status;
+}
+
+void Transaction::PrintTransactionInfo() const {
+	std::cout << clerkNumber << ' '
+		<< bankCard << ' '
+		<< sum << ' '
+		<< GetStatusStr().GetStr() << std::endl;
+}
+
+void Transaction::Export(std::ofstream& exportFile) const {
+	exportFile << sum << ','
+		<< bankCard << ','
+		<< clerkNumber << ','
+		<< status << std::endl;
+}
diff --git a/Week07/Exercise01/Transaction.h b/Week07/Exercise01/Transaction.h
new file mode 100644
index 0000000..d4941ce
--- /dev/null
+++ b/Week07/Exercise01/Transaction.h
@@ -0,0 +1,46 @@
+#ifndef _TRANSACTION
+#define _TRANSACTION
+
+#include "String.h"
+#include <fstream>
+
+const unsigned STATUS_PENDING = 0;
+const unsigned STATUS_ACCEPTED = 1;
+const unsigned STATUS_REJECTED = 2;
+
+// Няма да обвързваме транзакции с потребители директно
+// (т.е. няма член-данна която свързва User обект).
+// Тази връзка осъществяваме с UserTransaction класа.
+// Логически, можем да приемем че не искаме банковия служител
+// да знае за акаунтите на купувачите.
+class Transaction {
+	unsigned clerkNumber;
+	double sum;
+	unsigned bankCard;
+	// Уговаряме се, че стойността на status ще бъде равна на една
+	// от глобалните променливи STATUS_PENDING, STATUS_ACCEPTED и STATUS_REJECTED.
+	// Тук е добро място за употреба на енумерации (enum).
+	unsigned status;
+
+public:
+	Transaction(double sum, unsigned bankCard);
+	// Ако направим поне един конструктор, то конструктора по подразбиране
+	// спира да се създава автоматично
+	Transaction();
+
+	// Не искаме транзакции да могат да се променят своеволно.
+	// Т.е. след като се създаде транзакция, единствено можем да променяме статус
+	unsigned GetClerkNumber() const;
+	double GetSum() const;
+	unsigned GetBankCard() const;
+
+	unsigned GetStatus() const;
+	String GetStatusStr() const;
+	void SetStatus(unsigned clerk, unsigned status);
+
+	void PrintTransactionInfo() const;
+
+	void Export(std::ofstream& exportFile) const;
+};
+
+#endif /* _TRANSACTION */
diff --git a/Week07/Exercise01/User.cpp b/Week07/Exercise01/User.cpp
new file mode 100644
index 0000000..be5f76f
--- /dev/null
+++ b/Week07/Exercise01/User.cpp
@@ -0,0 +1,128 @@
+#include "User.h"
+#include <iostream>
+
+void User::copyFrom(const User& other) {
+	email = other.email;
+	password = other.password;
+	bankCard = other.bankCard;
+
+	libraryCount = other.libraryCount;
+	libraryAlloc = other.libraryAlloc;
+	library = new const Book*[libraryAlloc];
+	for (unsigned i = 0; i < libraryCount; ++i)
+		library[i] = other.library[i];
+}
+
+void User::free() {
+	delete[] library;
+}
+
+void User::resizeLibrary() {
+	libraryAlloc = libraryAlloc == 0 ? 8 : libraryAlloc * 2;
+	const Book** libraryLarger = new const Book*[libraryAlloc];
+
+	for (unsigned i = 0; i < libraryCount; ++i)
+		libraryLarger[i] = library[i];
+
+	delete[] library;
+	library = libraryLarger;
+}
+
+User::User() : email(), password(), bankCard(0), library(nullptr), libraryCount(0), libraryAlloc(0)
+{ }
+
+User::~User() {
+	free();
+}
+
+User::User(const User& other) {
+	copyFrom(other);
+}
+
+User& User::operator=(const User& other) {
+	if (this != &other) {
+		free();
+		copyFrom(other);
+	}
+	return *this;
+}
+
+User::User(User&& other) {
+	email = other.email;
+	password = other.password;
+	bankCard = other.bankCard;
+
+	library = other.library;
+	libraryCount = other.libraryCount;
+	libraryAlloc = other.libraryAlloc;
+
+	other.email.Clear();
+	other.password.Clear();
+	other.bankCard = 0;
+
+	other.library = nullptr;
+	other.libraryCount = other.libraryAlloc = 0;
+}
+
+User& User::operator=(User&& other) {
+	if (this != &other) {
+		free();
+
+		email = other.email;
+		password = other.password;
+		bankCard = other.bankCard;
+
+		library = other.library;
+		libraryCount = other.libraryCount;
+		libraryAlloc = other.libraryAlloc;
+
+		other.email.Clear();
+		other.password.Clear();
+		other.bankCard = 0;
+
+		other.library = nullptr;
+		other.libraryCount = other.libraryAlloc = 0;
+	}
+	return *this;
+}
+
+void User::SetEmail(const String& newEmail) {
+	email = newEmail;
+}
+
+const String& User::GetEmail() const {
+	return email;
+}
+
+void User::SetPassword(const String& newPassword) {
+	password = newPassword;
+}
+
+bool User::Login(const String& email, const String& password) {
+	return this->email.EqualTo(email) && this->password.EqualTo(password);
+}
+
+void User::AddBookToLibrary(const Book* book) {
+	if (libraryCount >= libraryAlloc)
+		resizeLibrary();
+	library[libraryCount++] = book;
+}
+
+void User::ListLibrary() {
+	for (unsigned i = 0; i < libraryCount; ++i) {
+		std::cout << '[' << i << "] ";
+		library[i]->PrintBookInfo();
+	}
+}
+
+const Book* User::GetBook(unsigned index) const {
+	return library[index];
+}
+
+void User::SetBankCard(unsigned newBankCard) {
+	bankCard = newBankCard;
+}
+
+unsigned User::GetBankCard() const {
+	return bankCard;
+}
diff --git a/Week07/Exercise01/User.h b/Week07/Exercise01/User.h
new file mode 100644
index 0000000..7e04560
--- /dev/null
+++ b/Week07/Exercise01/User.h
@@ -0,0 +1,45 @@
+#ifndef _USER
+#define _USER
+
+#include "String.h"
+#include "Book.h"
+
+class User {
+	String email;
+	String password;
+	unsigned bankCard;
+
+	// Масив от указатели към книги
+	const Book** library;
+	unsigned libraryCount;
+	unsigned libraryAlloc;
+
+	void copyFrom(const User& other);
+	void free();
+
+	void resizeLibrary();
+
+public:
+	User();
+	~User();
+	User(const User& other);
+	User& operator=(const User& other);
+	User(User&& other);
+	User& operator=(User&& other);
+
+	void SetEmail(const String& newEmail);
+	const String& GetEmail() const;
+
+	void SetPassword(const String& newPassword);
+
+	bool Login(const String& email, const String& password);
+
+	void AddBookToLibrary(const Book* book);
+	void ListLibrary();
+	const Book* GetBook(unsigned index) const;
+
+	void SetBankCard(unsigned newBankCard);
+	unsigned GetBankCard() const;
+};
+
+#endif /* _USER */
diff --git a/Week07/Exercise01/main.cpp b/Week07/Exercise01/main.cpp
new file mode 100644
index 0000000..ca97b15
--- /dev/null
+++ b/Week07/Exercise01/main.cpp
@@ -0,0 +1,382 @@
+#include "OnlineLibrary.h"
+#include "LibraryBanking.h"
+#include "Transaction.h"
+#include <iostream>
+
+// Игнорираме всички букви до края на реда вкл.
+void ignoreLine() {
+	while (std::cin.get() != '\n');
+}
+
+// Тази функция ни позволява да приемем от входа низ с неограничена дължина
+String getlineEndless() {
+	String bufferString;
+	for (char buffer = std::cin.get(); buffer != '\n'; buffer = std::cin.get()) {
+		bufferString.AppendChar(buffer);
+	}
+	return bufferString;
+}
+
+void RegisterConsole(OnlineLibrary& lib, LibraryBanking& libBank) {
+	char c;
+	std::cin >> c;
+	switch (c) {
+		case 'u': {
+				User newUser;
+
+				std::cout << "Username: ";
+				ignoreLine();
+				newUser.SetEmail(getlineEndless());
+
+				std::cout << "Password: ";
+				newUser.SetPassword(getlineEndless());
+
+				std::cout << "Bank card: ";
+				unsigned bankCard;
+				std::cin >> bankCard;
+				newUser.SetBankCard(bankCard);
+
+				lib.RegisterUser(newUser);
+			}
+			break;
+		case 'l': {
+				std::cout << "Librarian Number: ";
+				unsigned number;
+				std::cin >> number;
+
+				Librarian newLib(number);
+
+				std::cout << "Password: ";
+				ignoreLine();
+				newLib.SetPassword(getlineEndless());
+
+				lib.RegisterLibrarian(newLib);
+			}
+			break;
+		case 'c': {
+				std::cout << "Clerk Number: ";
+				unsigned number;
+				std::cin >> number;
+
+				BankClerk newClerk(number);
+
+				std::cout << "Static password: ";
+				ignoreLine();
+				newClerk.SetPassword(getlineEndless());
+
+				libBank.RegisterClerk(newClerk);
+			}
+			break;
+	}
+}
+
+void UserConsole(OnlineLibrary& lib, LibraryBanking& libBank) {
+	std::cout << "Username: ";
+	ignoreLine();
+	String bufferUsername = getlineEndless();
+
+	std::cout << "Password: ";
+	String bufferPassword = getlineEndless();
+
+	User* loggedIn = lib.LoginUser(bufferUsername, bufferPassword);
+	if (loggedIn == nullptr) {
+		std::cout << "Invalid username or password!" << std::endl;
+		return;
+	}
+
+	while (true) {
+		char c;
+		std::cin >> c;
+		switch (c) {
+			case 'e':
+				return;
+			case 'l':
+				loggedIn->ListLibrary();
+				break;
+			case 'r': {
+					std::cout << "User library index: ";
+					unsigned i;
+					std::cin >> i;
+					const Book* book = loggedIn->GetBook(i);
+
+					if (book == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else {
+						std::cout << book->GetText().GetStr() << std::endl;
+					}
+				}
+				break;
+			case 's':
+				lib.ListBooks();
+				break;
+			case 'p': {
+					std::cout << "Book index: ";
+					unsigned i;
+					std::cin >> i;
+					const Book* book = lib.GetBook(i);
+
+					if (book == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else if (loggedIn->GetBankCard() == 0 && book->GetPrice() != 0.0) {
+						std::cout << "Cannot purchase book with invalid card!" << std::endl;
+					}
+					else {
+						lib.PurchaseBook(*book, *loggedIn, libBank);
+						loggedIn->AddBookToLibrary(book);
+					}
+				}
+				break;
+			case 't':
+				lib.ListTransactions(*loggedIn);
+				break;
+			case 'x': {
+					std::cout << "Output file: ";
+					ignoreLine();
+					String fileName = getlineEndless();
+
+					lib.ExportTransactions(*loggedIn, fileName);
+				}
+				break;
+
+			case 'P': {
+					std::cout << "New password: ";
+					ignoreLine();
+					String newPassword = getlineEndless();
+
+					loggedIn->SetPassword(newPassword);
+				}
+				break;
+			case 'C': {
+					std::cout << "New bank card: ";
+					unsigned newBankCard;
+					std::cin >> newBankCard;
+
+					loggedIn->SetBankCard(newBankCard);
+				}
+				break;
+		}
+	}
+}
+
+void LibrarianConsole(OnlineLibrary& lib) {
+	std::cout << "Librarian number: ";
+	unsigned bufferLibrarianNo;
+	std::cin >> bufferLibrarianNo;
+
+	std::cout << "Password: ";
+	ignoreLine();
+	String bufferPassword = getlineEndless();
+
+	Librarian* loggedIn = lib.LoginLibrarian(bufferLibrarianNo, bufferPassword);
+	if (loggedIn == nullptr) {
+		std::cout << "Invalid librarian number or password!" << std::endl;
+		return;
+	}
+
+	while (true) {
+		char c;
+		std::cin >> c;
+		switch (c) {
+			case 'e':
+				return;
+			// Не се изисква по условие, но е удобно
+			case 's':
+				lib.ListBooks();
+				break;
+			case 'a': {
+					Book newBook;
+					newBook.SetAvailableForPurchase(true);
+
+					std::cout << "Title: ";
+					ignoreLine();
+					newBook.SetTitle(getlineEndless());
+
+					std::cout << "Author: ";
+					newBook.SetAuthor(getlineEndless());
+
+					std::cout << "Year: ";
+					short year;
+					std::cin >> year;
+					newBook.SetYear(year);
+
+					std::cout << "Price: ";
+					double price;
+					std::cin >> price;
+					newBook.SetPrice(price);
+
+					ignoreLine();
+					String text;
+					char prevprev = std::cin.get(), prev = std::cin.get(), curr = std::cin.get();
+					while (prevprev != '\n' || prev != '.' || curr != '\n') {
+						text.AppendChar(prevprev);
+						std::cout << '[' << (int)prevprev << ',' << (int)prev << ',' << (int)curr << ']' << std::endl;
+
+						prevprev = prev;
+						prev = curr;
+						curr = std::cin.get();
+					}
+					text.AppendChar(prevprev);
+					newBook.SetText(text);
+
+					lib.AddBook(newBook);
+				}
+				break;
+			case 'i': {
+					Book newBook;
+					newBook.SetAvailableForPurchase(true);
+
+					std::cout << "File name: ";
+					ignoreLine();
+					if (newBook.Import(getlineEndless())) {
+						double price;
+						std::cout << "Price: ";
+						std::cin >> price;
+						newBook.SetPrice(price);
+
+						lib.AddBook(newBook);
+					}
+				}
+				break;
+			case 'x': {
+					std::cout << "Book index: ";
+					unsigned i;
+					std::cin >> i;
+					Book* book = lib.GetBook(i);
+
+					if (book == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else {
+						std::cout << "File name: ";
+						ignoreLine();
+						book->Export(getlineEndless());
+					}
+				}
+				break;
+			case 'E': {
+					std::cout << "Book index: ";
+					unsigned i;
+					std::cin >> i;
+					Book* book = lib.GetBook(i);
+
+					if (book == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else {
+						ignoreLine();
+						std::cout << "Title: ";
+						book->SetTitle(getlineEndless());
+
+						std::cout << "Author: ";
+						book->SetAuthor(getlineEndless());
+
+						std::cout << "Price: ";
+						double price;
+						std::cin >> price;
+						book->SetPrice(price);
+					}
+				}
+				break;
+			case 'A': {
+					std::cout << "Book index: ";
+					unsigned i;
+					std::cin >> i;
+					Book* book = lib.GetBook(i);
+
+					if (book == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else {
+						book->SetAvailableForPurchase(! book->GetAvailableForPurchase());
+						if (book->GetAvailableForPurchase()) {
+							std::cout << "Book is now available!" << std::endl;
+						}
+						else {
+							std::cout << "Book is now not available!" << std::endl;
+						}
+					}
+				}
+				break;
+		}
+	}
+}
+
+void ClerkConsole(LibraryBanking& libBank) {
+	std::cout << "Clerk number: ";
+	unsigned bufferClerkNo;
+	std::cin >> bufferClerkNo;
+
+	std::cout << "Dynamic password: ";
+	unsigned dynamicPassword;
+	std::cin >> dynamicPassword;
+
+	ignoreLine();
+	std::cout << "Static password: ";
+	String bufferPassword = getlineEndless();
+
+	BankClerk* loggedIn = libBank.LoginClerk(bufferClerkNo, dynamicPassword, bufferPassword);
+	if (loggedIn == nullptr) {
+		std::cout << "Invalid clerk number or password!" << std::endl;
+		return;
+	}
+
+	while (true) {
+		char c;
+		std::cin >> c;
+		switch (c) {
+			case 'e':
+				return;
+			case 'l':
+				libBank.ListPendingTransactions();
+				break;
+			case 'A':
+			case 'R': {
+					std::cout << "Transaction index: ";
+					unsigned i;
+					std::cin >> i;
+					Transaction* transaction = libBank.GetTransaction(i);
+
+					if (transaction == nullptr) {
+						std::cout << "Invalid index!" << std::endl;
+					}
+					else if (transaction->GetStatus() != STATUS_PENDING) {
+						std::cout << "Transaction not pending!" << std::endl;
+					}
+					else {
+						transaction->SetStatus(loggedIn->GetClerkNumber(), c == 'A' ? STATUS_ACCEPTED : STATUS_REJECTED);
+					}
+				}
+				break;
+			case 'x': {
+					std::cout << "File name: ";
+					ignoreLine();
+					libBank.ExportNonPendingTransactions(getlineEndless());
+				}
+				break;
+		}
+	}
+}
+
+// Поискано ни е да имплементираме система,
+// това да направим конзолен интерфейс се подразбира
+int main() {
+	OnlineLibrary lib;
+	LibraryBanking libBank;
+
+	while (true) {
+		char c;
+		std::cin >> c;
+		switch (c) {
+			case 'r': RegisterConsole(lib, libBank); break;
+			case 'u': UserConsole(lib, libBank); break;
+			case 'l': LibrarianConsole(lib); break;
+			case 'c': ClerkConsole(libBank); break;
+			case 'e': return 0;
+			default: std::cout << "Invalid!" << std::endl;
+		}
+	}
+
+	return 0;
+}