#include <iostream>
using namespace std;

struct Node {
    int data;
    Node *prev;
};

struct List {
    int size;
    Node *head;
    Node *tail;
    Node *mid;
    void push(int n);
    void push_mid(int n);
    int pop();
    List();
};

List::List() {
    this->size = 0;
    this->head = 0;
    this->tail = 0;
    this->mid = 0;
}

void List::push(int n) {
    if (this->size == 0) {
        Node *temp = new Node;
        temp->data = n;
        temp->prev = 0;
        this->head = temp;
        this->tail = this->head;
        this->mid = this->head;
    } else {
        Node *temp = new Node;
        temp->data = n;
        temp->prev = 0;
        this->tail->prev = temp;
        this->tail = temp;
        if (this->size % 2 == 0) {
            this->mid = this->mid->prev;
        }
    }
    this->size++;
}

int List::pop() {
    int n = this->head->data;
    this->head = this->head->prev;
    this->size--;
    if (this->size % 2 == 1) {
        mid = mid->prev;
    }
    return n;
}

void List::push_mid(int n) {
    Node *temp = new Node;
    temp->data = n;
    this->size++;
    if (this->size == 1) {
        temp->prev = 0;
        this->head = temp;
        this->tail = this->head;
        this->mid = this->head;
    } else if (this->size == 2) {
        temp->prev = 0;
        this->head->prev = temp;
        this->tail = temp;
    } else if (this->size != 1 && this->size != 2) {
        temp->prev = this->mid->prev;
        this->mid->prev = temp;
        if (this->size % 2 == 1) {
            mid = mid->prev;
        }
    }
}

int main() {
    int n;
    cin >> n;
    List *Goblins = new List;
    for (int i = 0; i < n; ++i) {
        char com;
        cin >> com;
        if (com == '+') {
            int k;
            cin >> k;
            Goblins->push(k);
        } else if (com == '*') {
            int k;
            cin >> k;
            Goblins->push_mid(k);
        } else if (com == '-') {
            if (Goblins->size > 0) {
                cout << Goblins->pop() << endl;
            }
        }
    }
    return 0;
}