import java.util.InputMismatchException;
import java.util.Scanner;

public class Main {
    private static Scanner input = new Scanner(System.in);
    private static final int EXIT = -999;
    public static Restaurant restaurant;
    final static int ADD_EMPLOYEE = 1;
    final static int REMOVE_EMPLOYEE = 2;
    final static int IS_EMPLOYEE_EXIST = 3;
    final static int PRINT_EMPLOYEES = 4;
    final static int CHANGE_EMPLOYEE_AGE = 5;

    public static void main(String[] args) {
        System.out.println("Choose your option from the list below or if you want to stop enter -999");
        System.out.println("Press "+ADD_EMPLOYEE+" to add employee");
        System.out.println("Press "+REMOVE_EMPLOYEE+" to remove employee");
        System.out.println("Press "+IS_EMPLOYEE_EXIST+" to check if employee exist");
        System.out.println("Press "+PRINT_EMPLOYEES+" to print employees");
        System.out.println("Press "+CHANGE_EMPLOYEE_AGE+" to change age");

        int option = input.nextInt();
        while (option > 5 || (option < 1  && option!= EXIT )) {
            System.out.println("Wrong option number choose your option again");
            option = input.nextInt();
        }

        restaurant = new Restaurant();

        while (option != EXIT) {
            turn(option);

            System.out.println("Choose your option if you want to stop enter -999");
            option = input.nextInt();
            while (option > 5 || (option < 1  && option!= EXIT )) {
                System.out.println("Wrong option number choose your option again");
                option = input.nextInt();
            }
        }

    }

    private static void turn(int option) {
        switch (option) {
            case ADD_EMPLOYEE:
                addEmployee();

                break;
            case REMOVE_EMPLOYEE:
                removeEmployee();

                break;
            case IS_EMPLOYEE_EXIST:
                isEmployeeExist();

                break;
            case PRINT_EMPLOYEES:
                restaurant.printEmployees();

                break;
            case CHANGE_EMPLOYEE_AGE:
                changeEmployeeAge();

                break;
            default:
                break;
        }
    }

    private static void addEmployee() {
        String name;
        int age;

        System.out.println("Enter employee's name");
        name = input.next();
        System.out.println("Enter employee's age");
        age = input.nextInt();
        if (restaurant.addEmployee(name, age)) {
            System.out.println("You added the employee name to " + name + " and age to " + age);
        } else {
            if (name.isEmpty()) {
                System.out.println("You did not entered a name");
            } else {
                System.out.println("The employee " + name + " already exist");
            }
        }
    }

    private static void removeEmployee() {
        String name;

        System.out.println("Enter employee's name");
        name = input.next();
        if (restaurant.removeEmployee(name)) {
            System.out.println("You remvoed the employee " + name);
        } else {
            System.out.println("The employee " + name + " does not exist");
        }
    }

    private static void isEmployeeExist() {
        String name;

        System.out.println("Enter employee's name");
        name = input.next();
        if (restaurant.isEmployeeExist(name)) {
            System.out.println("Employee " + name + " exist");
        } else {
            System.out.println("Employee " + name + "  does not exist");
        }

    }

    private static void changeEmployeeAge() {
        String name;
        int age;

        System.out.println("Enter employee's name");
        name = input.next();
        System.out.println("Enter employee's age");
        age = input.nextInt();
        if (restaurant.setAge(name, age)) {
            System.out.println("You updated the employee " + name + " age to " + age);
        } else {
            System.out.println("The employee " + name + " does not exist");
        }
    }
}

import java.util.HashMap;

public class Restaurant {
    private HashMap<String, Integer> emploees;
    public Restaurant(){
        emploees = new HashMap<String, Integer>();
    }

    public boolean addEmployee(String name, int age) {
        if (this.isEmployeeExist(name) || name.isEmpty()) {
            return false;
        } else {
            this.emploees.put(name, age);
            return true;
        }
    }

    public boolean removeEmployee(String name) {
        if(this.isEmployeeExist(name)){
            this.emploees.remove(name);
            return true;
        }
        return false;
    }

    public boolean isEmployeeExist(String name){
        return (this.emploees.containsKey(name));
    }

    public void printEmployees() {
        if(this.emploees.isEmpty()){
            System.out.println("This restaurant has no workers");
        }
        else{
            for(String key : this.emploees.keySet()){
                System.out.println(key+" "+ this.emploees.get(key));

            }
        }

    }

    public boolean setAge(String name,int age){
        if(this.emploees.containsKey(name)){
            this.emploees.replace(name,age);
            return true;
        }
        return false;


    }



}