#include <iostream>

using namespace std;

struct Node {
    Node* next;
    Node* prev;
    int id;
};

struct Dequeue {
    Node* head = NULL;
    Node* tail = NULL;
    Node* centre = NULL;
    int size = 0;
};

void pushEnd(Dequeue* dequeue, int id) {
    Node* newNode = new Node {NULL, dequeue->tail, id};
    if (dequeue->size == 0) {
        dequeue->head = newNode;
        dequeue->centre = newNode;
    } else if (dequeue->size != 0) {
        dequeue->tail->next = newNode;
        if (dequeue->size % 2 == 0) {
            dequeue->centre = dequeue->centre->next;
        }
    }
    dequeue->tail = newNode;
    dequeue->size++;
}

void pop(Dequeue* dequeue) {
    Node* oldHead = dequeue->head;
    dequeue->head = dequeue->head->next;
    if (dequeue->size % 2 == 0) {
        dequeue->centre = dequeue->centre->next;
        dequeue->head->prev = NULL;
    }
    delete oldHead;
    dequeue->size--;
}

void pushCentre(Dequeue* dequeue, int id) {
    if (dequeue->size == 0) {
        pushEnd(dequeue, id);
        return;
    }
    Node* newNode = new Node {dequeue->centre->next, dequeue->centre, id};
    if (dequeue->size == 1) dequeue->tail = newNode;
    dequeue->centre->next = newNode;
    if (dequeue->size > 1) newNode->next->prev = newNode;
    if (dequeue->size % 2 == 0) dequeue->centre = newNode;
    dequeue->size++;
}

void clear(Dequeue* dequeue) {
    while (dequeue->size != 0) {
        pop(dequeue);
    }
    delete dequeue;
}

int main() {
    Dequeue* dequeue = new Dequeue;
    int numOfOper;
    cin >> numOfOper;
    for (int i = 0; i < numOfOper; ++i) {
        char curr;
        cin >> curr;
        if (curr == '+') {
            int id;
            cin >> id;
            pushEnd(dequeue, id);
        } else if (curr == '*') {
            int id;
            cin >> id;
            pushCentre(dequeue, id);
        } else if (curr == '-') {
            cout << dequeue->head->id << endl;
            pop(dequeue);
        }
    }
    clear(dequeue);
    return 0;
}