Answer to Question #276843 in C++ for Elyon

Question

School Library system

Problem Statement

You are a young tech-entrepreneur who provides technology solutions to challenges faced in the education sector of your country. You decide to build a school library management system that will allow a student to get registered, request to borrow a book from the library through the system and also put in a request to return the book, and a Librarian who will be there to approve requests and accept/check in returned books and update the system.

Required

1.

A Librarian should be able to do all the minimum roles stated, which are:

e.Change/Updatetheirownloginpassword.

f. Fine the students by debiting their library account balance if they have exceeded the number of days that they were to return book. (optional functionality)

Answer 1

#include <iostream>
#include <map>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;


void StudMenu()
{
    cout << "\tYou are in the school library management system.\n"
         << "\tPlease, select some of the following:\n"
         << "G - Get Registered\n"
         << "B - Request to borrow a book\n"
         << "R - Return a book\n"
         << "E - Exit menu\n";
    cout << "Your choice:";
}
void LibMenu()
{
    cout << "\tYou are in the school library management system.\n"
         << "\tPlease, select some of the following:\n"
         << "L - Login to the system\n"
         << "P - Process requests\n"
         << "E - Exit menu\n";
    cout << "Your choice:";
}
void MainMenu()
{
    cout << "\tYou are in the school library management system.\n"
         << "\t\tWho are you:\n";
    cout << "1 - Student\n"
         << "2 - Librarian\n"
         << "3 - Exit program\n";
    cout << "Your choice:";
}


struct Student
{
    string name;
    string passw;
    int fee;
    bool operator==(Student &s)
    {
        if (name == s.name && passw == s.passw)
            return true;
        else
            return false;
    }
};


void ReqRegUser(vector<Student> &Users, map<pair<string, string>, string> &responses)
{
    Student st;
    string name;
    cout << "\nEnter your name:";
    cin >> st.name;
    string passw;
    cout << "\nEnter your password:";
    cin >> st.passw;
    int fee;
    cout << "\nEnter a flat fee of 1000 shillings:";
    cin >> st.fee;
    Users.push_back(st);
    //Type of response
    string resp = "Reg";
    responses.insert(pair<pair<string, string>, string>({name, passw}, resp));
    cout << "Request submitted!";
}
void ReqBorrowBook(map<pair<string, string>, string> &responses)
{
    string nm;
    cout << "Enter your name: ";
    cin >> nm;
    string book;
    cout << "\nEnter a book to borrow:";
    cin >> book;
    string resp = "Bor";
    responses.insert(pair<pair<string, string>, string>({nm, book}, resp));
    cout << "Request submitted!";
}
void ReqReturnBook(map<pair<string, string>, string> &responses)
{
    string nm;
    cout << "Enter your name: ";
    cin >> nm;
    string book;
    cout << "\nEnter a book to return:";
    cin >> book;
    string resp = "Ret";
    responses.insert(pair<pair<string, string>, string>({nm, book}, resp));
    cout << "Request submitted!";
}


struct Librarian
{
    string name;
    string passw;
    Librarian(string _name, string _passw) : name(_name), passw(_passw) {}
    bool operator==(Librarian &l)
    {
        if (name == l.name && passw == l.passw)
            return true;
        else
            return false;
    }
};


bool LoginLibrarian(vector<Librarian> &Libers)
{
    string name;
    cout << "\nEnter your name:";
    cin >> name;
    string passw;
    cout << "\nEnter your password:";
    cin >> passw;
    Librarian temp(name, passw);
    for (vector<Librarian>::iterator it = Libers.begin(); it != Libers.end(); ++it)
    {
        if (*it == temp)
            return true;
    }
    return false;
}
void ReqProcess(map<pair<string, string>, string> &responses, vector<Student> &Users, vector<string> &books)
{


    cout << "You have this responses:\n";
    for (map<pair<string, string>, string>::iterator it = responses.begin(); it != responses.end(); ++it)
    {
        cout << it->second << " from " << it->first.first << " " << it->first.second << endl;
    }
    char ch;
    cout << "Process? [Y/N]";
    cin >> ch;
    if (ch == 'Y')
    {
        for (map<pair<string, string>, string>::iterator it = responses.begin(); it != responses.end(); ++it)
        {
            if (it->second == "Reg")
            {
                for (vector<Student>::iterator itu = Users.begin(); itu != Users.end(); ++itu)
                {
                    if (itu->name == it->first.first)
                    {
                        if (itu->fee < 1000)
                        {
                            cout << "User do not have deposit a flat fee of 1000 shillings\n";
                            Users.erase(itu);
                        }
                    }
                }


                responses.erase(it->first);
            }
            if (it->second == "Bor")
            {
                for (vector<Student>::iterator itu = Users.begin(); itu != Users.end(); ++itu)
                {
                    if (itu->name == it->first.first)
                    {
                        auto p = find(books.begin(), books.end(), it->first.second);
                        books.erase(p);
                    }
                }
                responses.erase(it->first);
            }
            if (it->second == "Ret")
            {
                books.push_back(it->first.second);
                responses.erase(it->first);
            }
        }
    }
}
int main()
{
    vector<Student> Users;


    vector<Librarian> Libers;
    Librarian l("Jack", "12345");
    vector<string> books{"Nature", "Bad Man", "Peolpe"};
    map<pair<string, string>, string> responses;
    char choice;
    do
    {
        MainMenu();
        cin >> choice;
        if (choice == '1')
        {
            char ch;
            do
            {
                StudMenu();
                cin >> ch;
                switch (ch)
                {
                case 'G':
                {
                    ReqRegUser(Users, responses);
                    break;
                }
                case 'B':
                {
                    ReqBorrowBook(responses);
                    break;
                }
                case 'R':
                {
                    ReqReturnBook(responses);
                    break;
                }
                }
            } while (ch != 'E');
        }
        else if (choice == '2')
        {
            char ch;
            do
            {
                bool check = false;
                LibMenu();
                cin >> ch;
                switch (ch)
                {
                case 'L':
                {
                    check = LoginLibrarian(Libers);
                    break;
                }
                case 'B':
                {
                    if (check)
                        ReqProcess(responses, Users, books);
                    else
                    {
                        cout << "You are not autorized to perform this operation!\n";
                    }
                    break;
                }
                }
            } while (ch != 'E');
        }
    } while (choice != '3');
}