using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

class Node
{
    public string NodeName;
    public List<Node> ChildNodes = new List<Node>();

    public Node(string name)
    {
        NodeName = name;
    }
}

class DFS
{
   static Dictionary<string, Node> nodes = new Dictionary<string, Node>();

    static void Main(string[] args)
    {
        string[] settings = Console.ReadLine().Split();
        int numNodes = int.Parse(settings[0]);
        int numSides = int.Parse(settings[1]);

        for (int i = 0; i < numNodes; i++)
        {
            string nodeName = Console.ReadLine();
            nodes.Add(nodeName, new Node(nodeName));
        }

        for (int i = 0; i < numSides; i++)
        {
            string[] pair = Console.ReadLine().Split();
            string fromNode = pair[0];
            string toNode = pair[1];

            nodes[fromNode].ChildNodes.Add(nodes[toNode]);
        }

        string[] nodeNames = nodes.Keys.ToArray();
        Array.Sort(nodeNames);

        Search(nodeNames);
    }

    static void Search(string[] graphNodes)
    {
        List<string> visited = new List<string>();

        while (graphNodes.Length > 0)
        {
            Node node = nodes[graphNodes.First()];
            if (!visited.Contains(node.NodeName))
            {
                visited.Add(node.NodeName);

            }
        }
    }
}