Challenge: Ticket Counter

Lab Java Beginner 10 points

Simulate a ticket queue. Read n commands: join <name> adds a person to the back; serve serves the person at the front and prints Served <name> (or Nobody waiting). At the end print Waiting: <count>.

Input

First n, then n commands.

Output

A line for each serve, then the waiting count.

Example

Input

5
join Asha
join Ravi
serve
join Meera
serve

Output

Served Asha
Served Ravi
Waiting: 1

Sample input available Sample output available

Editor

Java

Hints

A Queue gives people back in the order they joined.

Only read a name after the word join.

Solution explanation

offer adds at the back and poll removes from the front: first in, first out.

Show solution

import java.util.ArrayDeque;
import java.util.Queue;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        Queue<String> q = new ArrayDeque<>();
        for (int i = 0; i < n; i++) {
            String cmd = sc.next();
            if (cmd.equals("join")) {
                q.offer(sc.next());
            } else if (q.isEmpty()) {
                System.out.println("Nobody waiting");
            } else {
                System.out.println("Served " + q.poll());
            }
        }
        System.out.println("Waiting: " + q.size());
    }
}

Output

Answer