import java.util.Scanner;

public class WhichSystem {
    /* This application will help you determine
     * how much memory you need on the current
     * machine to do the task you report you
     * want to do.
     * The specifics are in the project description
     * file posted on the class web site.
     */
    public static void main(String[] args) {

        Scanner s = new Scanner(System.in);
            System.out.println("Users?");
                int users = s.nextInt();

        if (users < 1) {
            System.out.println("None needed");

        } else if (users >= 50) {
                System.out.println("Impossible");
        }

        if ((users >= 1) && (users > 50)) {

            System.out.println("System?");
                String operatingSystem = s.nextLine();

                    if (operatingSystem != "windows" + "linux" + "mac" ) {
                    System.out.println("Impossible");


                    }else {
                        System.out.println("Processes?");
                            int processes = s.nextInt();

                            if (processes <= 0) {
                                System.out.println("Impossible");
                                s.nextLine();

                            } else if (processes >= 100) {
                                System.out.println("Impossible");
                }



            }



    }}}