import java.util.*;

public class Dijkstra {
	static class Node implements Comparable<Node> {
		int index, time, freeze;
		boolean alreadyFreeze;
		Node(int index, int time, int freeze) {
			this.index = index;
			this.time = time;
			this.freeze = freeze;
		}
		Node(int index, int time,int freeze, boolean alreadyFreeze) {
			this(index,time,freeze);
			this.alreadyFreeze = alreadyFreeze;
		}
		public int compareTo(Node o) {
			return time - o.time;
		}
	}
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while(true) {
			int n = sc.nextInt(), m = sc.nextInt(),
			l = sc.nextInt(), K = sc.nextInt(),
			a = sc.nextInt(), h = sc.nextInt();
			if(n == 0) break;
			int[][] AM = new int[n][n];
			for(int i = 0; i < n; i++) { 
				Arrays.fill(AM[i], 1 << 28);
			}
			boolean[] isfreezer = new boolean[n];
			for(int i = 0; i < l; i++)
				isfreezer[sc.nextInt()] = true;
			for(int i = 0; i < K; i++) {
				int src = sc.nextInt(), des = sc.nextInt(), cost = sc.nextInt();
				AM[src][des] = AM[des][src] = cost;
			}
			Queue<Node> queue = new PriorityQueue<Node>();
			queue.add(new Node(a, 0, m));
			int ans = 1 << 28;
			boolean[][] check = new boolean[m + 1][n];
			while(!queue.isEmpty()) {
				Node node = queue.poll();
				if(check[node.freeze][node.index]) continue;
				check[node.freeze][node.index] = true;
				if(node.index == h) {
					ans = node.time;
					break;
				}
				for(int i = 0; i < n; i++) {
					if(i == node.index) continue;
					if(AM[node.index][i] <= node.freeze && 
							!check[node.freeze - AM[node.index][i]][i]) {
						queue.add(new Node(i, 
								node.time + AM[node.index][i], 
								node.freeze - AM[node.index][i]));
					}
				}
				if(isfreezer[node.index] && !node.alreadyFreeze) {
					for(int i = 1; i + node.freeze <= m; i++) {
						if(!check[i + node.freeze][node.index]) {
							queue.add(new Node(node.index, 
									node.time + i, node.freeze + i, true));
						} else break;
					}
				}
			}
			if(ans >= 1 << 28) {
				System.out.println("Help!");
			} else {
				System.out.println(ans);
			}
		}
	}
}