12F.cpp

#include <iostream>
#include <fstream>
#include <stdio.h>
using namespace std;

class Employee
{
private:
    int code;
    char name[20];
    float salary;

public:
    void read();
    void display();
    int getEmpCode() { return code; }
    int getSalary() { return salary; }
    void updateSalary(float s) { salary = s; }
};

fstream file;

void deleteExistingFile()
{
    remove("EMPLOYEE.DAT");
}

void appendToFile()
{
    Employee x;
    x.read();
    file.open("EMPLOYEE.DAT", ios::binary | ios::app);
    if (!file)
    {
        cout << "ERROR IN CREATING FILE\n";
        return;
    }
    file.write(reinterpret_cast<char *>(&x), sizeof(x));
    file.close();
    cout << "Record added successfully.\n";
}

void displayAll()
{
    Employee x;
    file.open("EMPLOYEE.DAT", ios::binary | ios::in);
    if (!file)
    {
        cout << "ERROR IN OPENING FILE\n";
        return;
    }
    while (file.read(reinterpret_cast<char *>(&x), sizeof(x)))
    {
        if (x.getSalary() >= 10000 && x.getSalary() <= 20000)
        {
            x.display();
        }
    }
    file.close();
}

void searchForRecord()
{
    Employee x;
    int c;
    int isFound = 0;
    cout << "Enter employee code: ";
    cin >> c;
    file.open("EMPLOYEE.DAT", ios::binary | ios::in);
    if (!file)
    {
        cout << "ERROR IN OPENING FILE\n";
        return;
    }
    while (file.read(reinterpret_cast<char *>(&x), sizeof(x)))
    {
        if (x.getEmpCode() == c)
        {
            cout << "RECORD FOUND\n";
            x.display();
            isFound = 1;
            break;
        }
    }
    if (isFound == 0)
    {
        cout << "Record not found!!!\n";
    }
    file.close();
}

void increaseSalary()
{
    Employee x;
    int c;
    int isFound = 0;
    float sal;
    cout << "Enter employee code: ";
    cin >> c;
    file.open("EMPLOYEE.DAT", ios::binary | ios::in);
    if (!file)
    {
        cout << "ERROR IN OPENING FILE\n";
        return;
    }
    while (file.read(reinterpret_cast<char *>(&x), sizeof(x)))
    {
        if (x.getEmpCode() == c)
        {
            cout << "Salary hike? ";
            cin >> sal;
            x.updateSalary(x.getSalary() + sal);
            isFound = 1;
            break;
        }
    }
    if (isFound == 0)
    {
        cout << "Record not found!!!\n";
    }
    file.close();
    cout << "Salary updated successfully." << endl;
}

void insertRecord()
{
    Employee x, newEmp;
    newEmp.read();
    fstream fin;
    file.open("EMPLOYEE.DAT", ios::binary | ios::in);
    fin.open("TEMP.DAT", ios::binary | ios::out);
    if (!file)
    {
        cout << "Error in opening EMPLOYEE.DAT file!!!\n";
        return;
    }
    if (!fin)
    {
        cout << "Error in opening TEMP.DAT file!!!\n";
        return;
    }
    while (file.read(reinterpret_cast<char *>(&x), sizeof(x)))
    {
        if (x.getEmpCode() > newEmp.getEmpCode())
        {
            fin.write(reinterpret_cast<char *>(&newEmp), sizeof(newEmp));
            newEmp = x;
        }
        else
        {
            fin.write(reinterpret_cast<char *>(&x), sizeof(x));
        }
    }
    fin.write(reinterpret_cast<char *>(&newEmp), sizeof(newEmp));
    fin.close();
    file.close();
    rename("TEMP.DAT", "EMPLOYEE.DAT");
    remove("TEMP.DAT");
    cout << "Record inserted successfully." << endl;
}

void Employee::read()
{
    cout << "Enter employee code: ";
    cin >> code;
    cout << "Enter name: ";
    cin.ignore(1);
    cin.getline(name, 20);
    cout << "Enter salary: ";
    cin >> salary;
}

void Employee::display()
{
    cout << code << " " << name << "\t" << salary << endl;
}

int main()
{
    char ch;
    deleteExistingFile();
    do
    {
        int n;
        cout << "ENTER CHOICE\n"
             << "1. ADD AN EMPLOYEE\n"
             << "2. DISPLAY\n"
             << "3. SEARCH\n"
             << "4. INCREASE SALARY\n"
             << "5. INSERT RECORD\n";
        cout << "Make a choice: ";
        cin >> n;
        switch (n)
        {
        case 1:
            appendToFile();
            break;
        case 2:
            displayAll();
            break;
        case 3:
            searchForRecord();
            break;
        case 4:
            increaseSalary();
            break;
        case 5:
            insertRecord();
            break;
        default:
            cout << "Invalid Choice\n";
        }
        cout << "Do you want to continue? (Y/N): ";
        cin >> ch;
    } while (ch == 'Y' || ch == 'y');
    return 0;
}