import java.io.*;
import java.util.ArrayList;

class Deque {

    public static int[] d;
    public static int head = 0;
    public static int tail = 0;
    private static int n;
    public static int count = 0;

    Deque(int n) {
        this.n = n;
        d = new int[n];
    }

    public static void pushFront(int data) {
        head = (head - 1 + n) % n;
        d[head] = data;
        count++;
    }

    public static void pushBack(int data) {
        d[tail] = data;
        tail = (tail + 1) % n;
        count++;
    }

    public static int popFront() {
        int ans = d[head];
        head = (head + 1) % n;
        count--;
        return ans;
    }

    public static int popBack() {
        tail = (tail - 1 + n) % n;
        count--;
        return d[tail];
    }

}

public class K {

    public static void main(String[] args) throws IOException {
        try (BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("kenobi.in")));
             PrintWriter pr = new PrintWriter(new FileOutputStream("kenobi.out"))) {
            int n = Integer.parseInt(br.readLine());
            Deque deque = new Deque(n);
            for (int i = 0; i < n; i++) {
                String[] buf = br.readLine().split(" ");
                switch (buf[0]) {
                    case "add":
                        deque.pushBack(Integer.parseInt(buf[1]));
                        break;
                    case "take":
                        deque.popBack();
                        break;
                    case "mum!":
                        for (int j = 0; j < deque.count / 2; j++) {
                           deque.pushBack(deque.popFront());
                        }
                        break;
                }
            }
            pr.println(deque.count);
            for (int i = deque.head; i < deque.tail; i++) {
                pr.print(deque.d[i] + " ");
            }
        }
    }
}