import sys

sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = 10**16
md = 998244353
# md = 10**9+7

from collections import deque

n, m, p = LI()
s, g = LI1()
to = [[] for _ in range(n)]
for _ in range(m):
    u, v = LI1()
    to[u].append(v)
    to[v].append(u)

def bfs(s):
    dist = [[inf]*2 for _ in range(n)]
    dist[s][0] = 0
    q = deque()
    q.append((s, 0))
    while q:
        u, p = q.popleft()
        d = dist[u][p]
        for v in to[u]:
            if dist[v][1-p] == inf:
                dist[v][1-p] = d+1
                q.append((v, 1-p))
    return dist

ds = bfs(s)
dg = bfs(g)
parity = p & 1
ans = []
for u in range(n):
    if ds[u][0]+dg[u][parity] <= p or ds[u][1]+dg[u][1-parity] <= p:
        ans.append(u+1)

if ans:
    print(len(ans))
    for a in ans: print(a)
else:
    print(-1)