Homework Mike

package com.company;

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int select = 0;
        int input = 0;
        int max = 0;
        int min = 0;
        boolean first = true;
        while (select != 4) {
            System.out.println("Please choose an option:");
            System.out.println("1. Enter a number: ");
            System.out.println("2. Print the greatest number");
            System.out.println("3. Print the smallest number");
            System.out.println("4. Exit program.");
            select = scanner.nextInt();

            if (input > max)
                max = input;
            if (input < min)
                min = input;

            switch (select) {
                case 1:
                    System.out.print("Enter an integer: ");
                    input = scanner.nextInt();
                    if (first) {
                        min = input;
                        max = input;
                        first = false;
                    }
                    break;
                case 2:
                    System.out.println(max);
                    if (first) {
                        System.out.println("Please enter a first number");
                    }
                    break;
                case 3:
                    System.out.println(min);
                    if (first) {
                        System.out.println("Please enter a first number");
                    }
                    break;
                case 4:
                    System.out.println("The program will now exit, bye!");
                    break;
                default:
                    System.out.println("Invalid number");
                    break;
            }
        }
    }
}