import sys; input = sys.stdin.buffer.readline
sys.setrecursionlimit(10**7)
from collections import defaultdict
from heapq import heappop, heappush
INF = float('inf')

def getlist():
	return list(map(int, input().split()))

class Graph(object):
	def __init__(self):
		self.graph = defaultdict(list)

	def __len__(self):
		return len(self.graph)

	def add_edge(self, a, b, w):
		self.graph[a].append((b, w))

class Dijkstra(object):
	def __init__(self, graph, s):
		self.g = graph.graph
		self.dist = defaultdict(lambda: INF); self.dist[s] = 0
		self.prev = defaultdict(lambda: None)
		self.dic = defaultdict(lambda:[10 ** 10])
		self.dic[s].append(s)
		self.Q = []
		heappush(self.Q, (self.dist[s], s))
		while self.Q:
			dist_u, u = heappop(self.Q)
			if self.dist[u] < dist_u:
				continue
			for v, w in self.g[u]:
				alt = dist_u + w
				if self.dist[v] > alt:
					self.dist[v] = alt
					self.prev[v] = u
					self.dic[v] = self.dic[u] + [v]
					heappush(self.Q, (alt, v))
				elif self.dist[v] == alt:
					if self.dic[u] + [v] < self.dic[v]:
						self.prev[v] = u
						self.dic[v] = self.dic[u] + [v]
						heappush(self.Q, (alt, v))

	def s_p(self, goal):
		path = []
		node = goal
		while node is not None:
			path.append(node)
			node = self.prev[node]
		return path[::-1]

#処理内容
def main():
	N, M, s, g = getlist()
	G = Graph()
	for i in range(M):
		a, b, w = getlist()
		G.add_edge(a, b, w)
		G.add_edge(b, a, w)

	D = Dijkstra(G, s)
	ans = D.dic[g][1:]
	# print(D.dic[g])
	print(*ans)




if __name__ == '__main__':
	main()