import queue
N,M,P=map(int,input().split())
S,G=map(int,input().split())
g=[[] for _ in range(N+1)]
for i in range(M):
    u,v=map(int,input().split())
    g[u].append(v)
    g[v].append(u)

def bfs(src):
    dist=[[10**20]*(N+1) for _ in range(2)]
    vis=[[False]*(N+1) for _ in range(2)]
    dist[0][src]=0
    q=queue.Queue()
    q.put(src)
    while not q.empty():
        cur=q.get()
        for dst in g[cur]:
            for i in range(2):
                nd=dist[i][cur]+1
                if nd<dist[nd%2][dst]:
                    dist[nd%2][dst]=nd
                    q.put(dst)
    return dist

dist_src=bfs(S)
dist_dst=bfs(G)
ans_set=set()
for i in range(N+1):
    find=False
    for j in range(2):
        for k in range(2):
            if (j+k)%2 != P%2:
                continue
            if dist_src[j][i]+dist_dst[k][i]<=P:
                ans_set.add(i)
ans=list(ans_set)
ans.sort()
if len(ans)==0:
    print(-1)
else:
    print(len(ans))
    for a in ans:
        print(a)