/********************************************
***     Solution by Bekzhan Kassenov      ***
********************************************/

#include <iostream>
#include <cstdio>
#include <fstream>
#include <sstream>
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <algorithm>
#include <functional>
#include <math.h>
#include <time.h>
#include <stdlib.h>
#include <iomanip>

using namespace std;

#define sqr(x) (x) * (x)
#define PII pair <int, int>
#define F first
#define S second
#define MP make_pair
#define PB push_back
#define VI vector <int>
#define VII vector <VI>
#define ll long long
#define ull unsigned long long
#define INF
#define MOD
#define EPS
#define File "kenobi"

struct item
{
    int val;
    item *pred, *next;

    item(item *a)
        {
            val = a -> val;
            pred = a -> pred;
            next = a -> next;
        }

    item()
        {
            pred = NULL, next = NULL;
        }

    item(int v, item *a)
        {
            next = NULL;
            pred = a;
            val = v;
        }
};

typedef item * pitem;

pitem beg = NULL, en = NULL, middle = NULL;

int size;

void add(int val)
{
    if (size == 0)
        {
            beg = new item();

            beg -> val = val;
            en = beg;
            middle = beg;
            return;
        }

    pitem tmp = new item(val, en);
    en -> next = tmp;
    en = tmp;
}

void take()
{
    if (size == 0)
        return;

    if (size == 1)
        {
            delete en;
            delete beg;
            beg = NULL;
            return;
        }

    pitem tmp = en -> pred;
    tmp -> next = NULL;

    delete en;

    en = tmp;
}

void mum()
{
    if (size < 2)
        return;

    pitem nen = middle -> pred;
    middle -> pred = NULL;
    nen -> next = NULL;

    beg -> pred = en;
    en -> next = beg;

    swap(beg, middle);

    if (size % 2)
        middle = en;

    en = nen;
}

void print()
{
    printf("%d\n", size);

    for (pitem it = beg; it != NULL; it = it -> next)
       printf("%d ", it -> val);

    printf("\n");
}

int main()
{
    freopen(File".in", "r", stdin);
    freopen(File".out", "w", stdout);

    int n;

    scanf("%d", &n);

    size = 0;

    int tmp;

    char s[4];

    for (int i = 0; i < n; i++)
        {
           scanf("\n%s", s);

            if (s[0] == 'a')
                {
                    scanf("%d", &tmp);

                    add(tmp);
                    size++;
                    if (size % 2 == 0)
                        middle = middle -> next;
                }

            if (s[0] == 't')
                {
                    if (size > 0)
                        {
                            if (size % 2 == 0)
                                middle = middle -> pred;

                            take();
                            size--;
                       }
                }

            if (s[0] == 'm')
                {
                    mum();
                }
        }

    print();

    return 0;
}