import java.util.*;

class Player {

    @SuppressWarnings("unchecked")
    public static void main(String args[]) {

        final Scanner in = new Scanner(System.in);
        final int nodeCount = in.nextInt(); // the total number of nodes in the level, including the gateways
        final int linkCount = in.nextInt(); // the number of links
        final int exitCount = in.nextInt(); // the number of exit gateways

        final Set<Integer>[] connections = (Set<Integer>[]) new Set[nodeCount];

        for (int i = 0; i < linkCount; i++) {
            final int N1 = in.nextInt(); // N1 and N2 defines a link between these nodes
            if (connections[N1] == null) {
                connections[N1] = new HashSet<>();
            }
            final int N2 = in.nextInt();
            if (connections[N2] == null) {
                connections[N2] = new HashSet<>();
            }

            connections[N1].add(N2);
            connections[N2].add(N1);
        }

        final Set<Integer> exits = new HashSet<>();
        for (int i = 0; i < exitCount; i++) {
            final int exit = in.nextInt(); // the index of a gateway node
            exits.add(exit);
        }


        Queue<Integer> toVisit = new LinkedList<>();
        Set<Integer> alreadyChecked = new HashSet<>();
        int[] prevIndex = new int[nodeCount];
        boolean found;

        // game loop
        while (true) {
            final int agentIndex = in.nextInt(); // The index of the node on which the Skynet agent is positioned this turn

            Arrays.fill(prevIndex, -1);
            toVisit.clear();
            alreadyChecked.clear();
            toVisit.add(agentIndex);
            alreadyChecked.add(agentIndex);
            found = false;

            while (!toVisit.isEmpty() && !found) {
                int current = toVisit.poll();
                Set<Integer> neighbors = connections[current];
                if (neighbors == null) {
                    continue;
                }
                for (int neighbor : neighbors) {
                    if (alreadyChecked.contains(neighbor)) {
                        continue;
                    }
                    prevIndex[neighbor] = current;
                    if (exits.contains(neighbor)) {
                        current = neighbor;
                        while (prevIndex[current] != agentIndex) {
                            current = prevIndex[current];
                        }
                        System.out.println(agentIndex + " " + current);
                        found = true;
                        connections[agentIndex].remove(current);
                        connections[current].remove(agentIndex);
                        break;
                    }
                    alreadyChecked.add(neighbor);
                    toVisit.add(neighbor);
                }
            }
        }
    }

}