#include <iostream>
#include <vector>

using namespace std;

int main() {
    string rec;
    vector<string> valjaju;
    while(cin>>rec) {
        int n = rec.size();
        if(n < 3 || n > 20) continue;
        if(rec[0] == '0' && (rec[1] == 'x' || rec[1] == 'X')) {
            bool valja = true;
            for(int i = 2; i < n; i++) {
                char c = rec[i];
                if(!((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <='F'))) {
                    valja = false;
                    break;
                }
            }
            if(valja) valjaju.push_back(rec);
        }
    }
    int v_size = valjaju.size();
    if(v_size == 0) {
        cout << "" << endl;
        return 0;
    }
    cout << valjaju[0];
    for(int i = 1; i < v_size; i++) {
        cout << " " << valjaju[i];
    }
    cout << endl;
}