import java.util.*;
public class RunPFSearchDirected {
    static Node[] nodes;
    static int src;
    static int dst;
    public static void main(String[] args) {
	doInput();
	PFSearch dj = new PFSearch(nodes);
	dj.solve(nodes[src],nodes[dst]);
	System.out.println(dj.nodes[dst]);
	// System.out.println(Node.toString(dj.getPath(dst)));
    }
    static void doInput() {
	Scanner sc = new Scanner(System.in);
	int nTown = sc.nextInt(); // 都市の数
	int nRoute = sc.nextInt(); // 道路の数

	nodes = new Node[nTown];
	for (int i=0; i<nTown; i++) nodes[i] = new Node(i);
	for (int i=0; i<nRoute; i++) {
	    int from = sc.nextInt();
	    int to = sc.nextInt();
	    double len = sc.nextDouble();
	    nodes[from].edges.add(new Edge(nodes[from],nodes[to],len));
	}
	src = sc.nextInt();	// 出発地点
	dst = sc.nextInt();	// 到着地点
    }
}