#include <iostream>
#include <sstream>
#include <string>
#include <memory>

using namespace std;

void removeNegative(unique_ptr<int[]>& ptr, int& n) {
    for (int i = 0; i < n; i++) {
        if (ptr[i] < 0) {
            for (int j = i; j < n - 1; j++) {
                ptr[j] = ptr[j + 1];
            }
            n--;
            i--;
        }
    }
}

void reverse(unique_ptr<int[]>& ptr, int& n) {
    int number, count = n / 2;
    for (int i = 0; i < count; i++) {
        number = ptr[i];
        ptr[i] = ptr[n - (1 + i)];
        ptr[n - (1 + i)] = number;
    }
}

int main() {
    string line;
    getline(cin, line);

    istringstream ss(line);

    unique_ptr<int[]> numbers = make_unique<int[]>(1000);

    int number, counter;

    for (counter = 0; counter < 1000 && ss >> number; ++counter) {
        numbers[counter] = number;
    }

    removeNegative(numbers, counter);

    if (counter == 0) {
        cout << "empty";
    }
    else {
        reverse(numbers, counter);
        for (int i = 0; i < counter; i++) {
            cout << numbers[i] << ' ';
        }
    }

    cout << endl;
    return 0;
}