import heapq
N,M,S,G=map(int,input().split())
L=[[] for _ in range(N)]
for _ in range(M):
    a,b,c=map(int,input().split())
    L[a].append([b,c])
    L[b].append([a,c])
q=[[0,[S]],[1e9,[]]]
d={}
while True:
    e,n=heapq.heappop(q)
    t=n[-1]
    if t not in d:
        d[t]=True
        if t==G: break
        for j,i in L[t]: heapq.heappush(q,[i+e,n+[j]])
print(" ".join(map(str,n)))