from math import sqrt,sin,cos,tan,ceil,radians,floor,gcd,exp,log,log10,log2,factorial,fsum
from heapq import heapify, heappop, heappush
from bisect import bisect_left, bisect_right
from copy import deepcopy
import copy
import random
from collections import deque,Counter,defaultdict
from itertools import permutations,combinations
from decimal import Decimal,ROUND_HALF_UP
#tmp = Decimal(mid).quantize(Decimal('0'), rounding=ROUND_HALF_UP)
from functools import lru_cache, reduce
#@lru_cache(maxsize=None)
from operator import add,sub,mul,xor,and_,or_,itemgetter
import sys
input = sys.stdin.readline
# .rstrip()
INF = 10**18
mod1 = 10**9+7
mod2 = 998244353

#DecimalならPython
#再帰ならPython!!!!!!!!!!!!!!!!!!!!!!!!!!


'''
dfsじゃないといけないかも
頂点Gまでの経路
まあ普通にP回まで探索すればいいけど
それまでに通った辺をどうやって管理するか
重複していいならリストでいいのか
'''

N,M,P = map(int, input().split())
S,Go = map(int, input().split())

G = [[] for _ in range(N+1)]

for _ in range(M):
    u,v = map(int, input().split())
    G[u].append(v)
    G[v].append(u)

Q = deque()
Q.append((S,[]))
ans = set()

while len(Q) > 0:
    pos = Q[0][0]
    ls = deepcopy(Q[0][1])
    Q.popleft()
    
    ls.append(pos)
    
    if len(ls) > P+1:
        break
    if len(ls) == P+1:
        if pos == Go:
            for i in ls:
                ans.add(i)
        continue
    
    for nx in G[pos]:
        Q.append((nx,ls))

if len(ans) == 0:
    print(-1)
    exit()

print(len(ans))
ans = list(ans)
ans.sort()
for a in ans:
    print(a)