cf100127B

#include <algorithm>
#include <numeric>
#include <string>
#include <cstring>
#include <set>
#include <map>
#include <vector>
#include <queue>
#include <iostream>
#include <iterator>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <sstream>

using namespace std;

typedef long long ll;
typedef vector<int> VI;
typedef vector<vector<int> > VVI;
typedef pair<int, int> PII;


#define FOR(i, x, y) for(ll i=x; i<=y; i++)
#define FORD(i, x, y) for (ll i = x; i >= y; --i)
#define REP(i, n) for(ll i=0; i<n; i++)
#define REPD(i, n) for(ll i = n - 1; i >= 0; --i)

#define ALL(c) (c).begin(), (c).end()
#define SORT(c) sort(ALL(c))
#define UNIQ(c) SORT(c),(c).resize(unique(ALL(c))-(c).begin())
#define SZ(c) (int)(c).size()

#define CLEAR(x) memset(x,0,sizeof x)
#define FILL(x,v) memset(x,v,sizeof x)

#define pb push_back
#define mp make_pair
#define X first
#define Y second



const double eps = 1.0e-11;
const double pi = acos(-1.0);

struct Node {
	int value;
	Node *next, *prev;
	Node (int index) : value(index), next(NULL), prev(NULL) {}
};

struct List {
	Node *begin, *middle, *end;
	size_t size;
	List() : begin(NULL), middle(NULL), end(NULL), size(0) {}
	void Add(int index) {
		if (!begin) {
			size = 1;
			begin = new Node(index);
			end = middle = begin;
			return;
		}
		end->next = new Node(index);
		end->next->prev = end;
		end = end->next;
		++size;
		if (size % 2 == 0)
			middle = middle->next;
	}
	void Remove() {
		if (size > 1) {
			end = end->prev;
			end->next = NULL;
			if (size % 2 == 0)
				middle = middle->prev;
			--size;
			return;
		}
		begin = middle = end = NULL;
	}
	void Shuffle() {
		if (size < 2)
			return;
		end->next = begin;
		begin->prev = end;
		begin = middle;
		Node* tmp = middle;
		middle = end;
		if (size % 2 == 0)
			middle = middle->next;
		end = tmp->prev;
		begin->prev = NULL;
		end->next = NULL;
	}
	void Print() {
		Node* tmp = begin;
		vector<int> res;
		while(tmp) {
			res.push_back(tmp->value);
			tmp = tmp->next;
		}
		cout << res.size() << endl;
		//cout << middle->value << endl;
		REP(i, SZ(res))  {
			if (i)
				cout << " ";
			cout << res[i];
		}
		cout << endl;
	}
};


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

	int n;
	List l;
	cin >> n;
	REP(i, n) {
		string q;
		cin >> q;
		if (q == "add") {
			int index;
			cin >> index;
			l.Add(index);
			//continue;
		}
		if (q == "take") {
			l.Remove();
			//continue;
		}
		if (q == "mum!") {
			l.Shuffle();
		}
		//l.Print();
	}
	l.Print();
	return 0;
}