Library system

#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
using namespace std;

struct Book
{
    char name[50];
    int ID;
    char author[50];
    double price;
    int copies;
};

ofstream OLib("Library.txt", ios::app);
ifstream iLib("Library.txt", ios::in);

void SearchByID(int y);
void SearchByName(char y[]);

int main()
{
    string search, line;
    int choice;
    Book book;
    cout << setw(310) << "Library system by MiDo\n" << endl;
    cout << "Choose one of the following:- " << endl;
    cout << "1. Add a new book.\n2. Update a book.\n3. Delete a book.\n4. Show all books.\n5. Search book by ID.\n6. Search book by Name.\n7. Borrow a book.\n8. Exit." << endl;
    cin >> choice;
    while (choice >= 0 && choice <8) {
        if (choice == 1) {
            cout << "Enter the name of the book you want to add: " << endl;
            getchar();
            cin.get(book.name, 50);
            cout << "Enter the ID of the book you want to add: " << endl;
            cin >> book.ID;
            cout << "Enter the author of the book you want to add: " << endl;
            getchar();
            cin.get(book.author, 50);
            cout << "Enter the price of the book you want to add: " << endl;
            cin >> book.price;
            cout << "Enter the copies of the book you want to add: " << endl;
            cin >> book.copies;
            OLib << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
            cout << "Book successfully added!" << endl;
            choice = 0;
        }
        else if (choice == 2) {
            cout << "Enter the ID of the book you want to update." << endl;
            cin >> search;
            while (getline(iLib, line)) {
                if (line.find(search)) {
                    line.replace(line.find(search), search.length(), "");
                    cout << "Enter the new ID, name, author, price, copies" << endl;
                    cin >> book.ID >> book.name >> book.author >> book.price >> book.copies;
                    OLib << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
                    cout << "Book successfully edited!" << endl;
                }
            }
        }
        else if (choice == 3) {
        }
        else if (choice == 4) {
            string id, name, author, price, copies;
            iLib >> id >> name >> author >> price >> copies;
            cout << left << setw(4) << id << setw(15) << name << setw(15) << author << setw(8) << price << setw(8) << copies << endl;
            while (iLib >> book.ID >> book.name >> book.author >> book.price >> book.copies) {
                cout << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
                cout << "================================================" << endl;
            }
            choice = 0;
        }
        else if (choice == 5) {
            int x;
            cout << "Enter the ID you want to search for" << endl;
            cin >> x;
            SearchByID(x);
            choice = 0;
        }
        else if (choice == 6) {
            char x[50];
            cout << "Enter the book name you want to search for" << endl;
            cin >> x;
            SearchByName(x);
            choice = 0;
        }
        else if (choice == 7) {
            int x;
            cout << "Enter the ID of the book you want to borrow" << endl;
            cin >> x;

        }
        else if (choice == 8) {
            return 0;
        }
        cout << "1. Add a new book.\n2. Update a book.\n3. Delete a book.\n4. Show all books.\n5. Search book by ID.\n6. Search book by Name.\n7. Borrow a book.\n8. exit." << endl;
        cin >> choice;
    }
    cout << "Program ended!" << endl;
    system("pause");
    return 0;
}

void SearchByID(int y)
{
    bool found = false;
    Book book;
    string id, name, author, price, copies;
    iLib >> id >> name >> author >> price >> copies;
    while (iLib >> book.ID >> book.name >> book.author >> book.price >> book.copies) {
        if (book.ID == y) {
            cout << "Book is found:" << endl;
            cout << left << setw(4) << id << setw(15) << name << setw(15) << author << setw(8) << price << setw(8) << copies << endl;
            cout << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
            found = true;
            break;
        }
    }
    if (found == false)
        cout << "Book is not found" << endl;
}

void SearchByName(char y[])
{
    bool found = false;
    Book book;
    string id, name, author, price, copies;
    iLib >> id >> name >> author >> price >> copies;
    while (iLib >> book.ID >> book.name >> book.author >> book.price >> book.copies) {
        if (strcmp(y,book.name) == 0) {
            cout << "Book is found:" << endl;
            cout << left << setw(4) << id << setw(15) << name << setw(15) << author << setw(8) << price << setw(8) << copies << endl;
            cout << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
            found = true;
            break;
        }
    }
    if (found == false)
        cout << "Book is not found" << endl;
}

void Borrow(int x)
{
    bool found = false;
    Book book;
    int b;
    string id, name, author, price, copies;
    iLib >> id >> name >> author >> price >> copies;
    while (iLib >> book.ID >> book.name >> book.author >> book.price >> book.copies) {
        if (book.ID == x) {
            b = book.copies;
            cout << "Book is borrowed:" << endl;
            cout << left << setw(4) << id << setw(15) << name << setw(15) << author << setw(8) << price << setw(8) << copies << endl;
            cout << left << setw(4) << book.ID << setw(15) << book.name << setw(15) << book.author << setw(8) << book.price << setw(8) << book.copies << endl;
            found = true;
            break;
        }
    }
    if (found == false)
        cout << "Book is not found" << endl;
}