#include <fstream>
struct Node{
    int value;
    Node* next;
};

void PushBack(Node* &prev, int digit) {
    Node *cur = new Node;
    cur->value = digit;
    cur->next = prev;
    prev = cur;
}

int PopBack(Node* &cur) {
    int digit = cur->value;
    Node *temp = cur;
    cur = cur->next;
    delete temp;
    return digit;
}

int main() {
    std::ifstream in;
    std::ofstream out;
    in.open("input.txt");
    out.open("output.txt");
    int n;
    in >> n;
    Node* stack = new Node;
    char operation;
    int digit;
    for (int i = 0; i < n; i++) {
        in >> operation;
        if (operation=='+') {
            in >> digit;
            PushBack(stack, digit);
        }
        else {
            if (operation=='-') {
                out << PopBack(stack) << std::endl;
            }
        }
    }
    out.close();
    return 0;
}