#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <algorithm>

using namespace std;

/**
 * Auto-generated code below aims at helping you parse
 * the standard input according to the problem statement.
 **/

typedef map<int, pair<bool, vector<int>* >* > MapLinks;
typedef pair<int, pair<bool, vector<int>* >* > PairLink;
typedef pair<bool, vector<int>* > PairNode;
typedef vector<int>* Nodes;

int main()
{
    int N; // the total number of nodes in the level, including the gateways
    int L; // the number of links
    int E; // the number of exit gateways

    MapLinks links;
    MapLinks::iterator it;
    MapLinks::iterator it2;
    pair<bool, vector<int>* >* p;

    cin >> N >> L >> E; cin.ignore();
    for (int i = 0; i < L; i++) {
        int N1; // N1 and N2 defines a link between these nodes
        int N2;
        cin >> N1 >> N2; cin.ignore();

        it = links.find(N1);
        if(it == links.end()) {
            p = new PairNode(false, new vector<int>());
            it = (links.insert(PairLink(N1, p))).first;
        }
        it->second->second->push_back(N2);

        it = links.find(N2);
        if(it == links.end()) {
            p = new PairNode(false, new vector<int>());
            it = (links.insert(PairLink(N2, p))).first;
        }
        it->second->second->push_back(N1);

    }

    for (int i = 0; i < E; i++) {
        int EI; // the index of a gateway node
        cin >> EI; cin.ignore();
        links[EI]->first = true;
    }

    // print links
    for(it = links.begin(); it != links.end(); ++it) {
        cerr << it->first << " : " << it->second->first << endl;

        for(vector<int>::iterator ite = it->second->second->begin(); ite != it->second->second->end(); ++ite) {
            cerr << *ite << " ";
        }
        cerr << endl;
    }

    // game loop
    while (1) {
        int SI; // The index of the node on which the Skynet agent is positioned this turn
        cin >> SI; cin.ignore();

        cerr << "========" << endl << SI << endl;

        Nodes nodes;
        bool b = false;

        it = links.find(SI);
        if(it == links.end()) {
            continue;
        }

        nodes = it->second->second;

        for(vector<int>::iterator ite = nodes->begin(); ite != nodes->end(); ++ite) {
            *ite;
            it2 = links.find(*ite);
            if(it2 != links.end()) {
                if(it2->second->first) {
                    cout << to_string(SI) << " " << to_string(*ite) << endl;
                    b = true;
                    break;
                }
                cerr << *ite << " : " << it2->second->first << endl;
            }
        }

        if(!b) {
            cout << to_string(SI) << " " << to_string(nodes->front()) << endl;
        }
    }
}