import sys; input = sys.stdin.buffer.readline
sys.setrecursionlimit(10**7)
from collections import defaultdict
from collections import deque
INF = float("inf")

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

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

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

class BFS(object):
	def __init__(self, graph, s, N):
		self.g = graph.graph
		self.Q = deque(); self.Q.append(s)
		self.dist = [INF] * N; self.dist[s] = 0
		while self.Q:
			v = self.Q.popleft()
			for i in self.g[v]:
				if self.dist[i] == INF:
					self.dist[i] = self.dist[v] + 1
					self.Q.append(i)

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

#処理内容
def main():
	N, M, P = getlist()
	s, g = getlist()
	s -= 1; g -= 1
	G = Graph()
	for i in range(M):
		a, b = getlist()
		a -= 1; b -= 1
		G.add_edge(a, b + N)
		G.add_edge(b + N, a)
		G.add_edge(b, a + N)
		G.add_edge(a + N, b)

	cnt = 0
	ans = []
	BF1 = BFS(G, s, 2 * N)
	BF2 = BFS(G, g, 2 * N)
	dist1 = BF1.dist
	dist2 = BF2.dist
	if P % 2 == 0:
		for i in range(N):
			if dist1[i] + dist2[i] <= P or dist1[i + N] + dist2[i + N] <= P:
				cnt += 1
				ans.append(i + 1)

	else:
		for i in range(N):
			if dist1[i] + dist2[i + N] <= P or dist1[i + N] + dist2[i] <= P:
				cnt += 1
				ans.append(i + 1)

	if cnt == 0:
		print(-1)
		return

	print(cnt)
	for i in ans:
		print(i)


if __name__ == '__main__':
	main()