import collections
import heapq
from operator import or_


class Dijkstra:
    def __init__(self):
        self.e = collections.defaultdict(list)

    def add(self, u, v, d):
        self.e[u].append([v, d])
        self.e[v].append([u, d])

    def delete(self, u, v):
        self.e[u] = [_ for _ in self.e[u] if _[0] != v]
        self.e[v] = [_ for _ in self.e[v] if _[0] != u]

    def search(self, s):
        """
        :param s: 始点
        :return: 始点から各点までの最短経路
        """
        d = collections.defaultdict(lambda: float('inf'))
        d[s] = 0
        q = []
        heapq.heappush(q, (0, s))
        v = collections.defaultdict(bool)
        while len(q):
            k, u = heapq.heappop(q)
            if v[u]:
                continue
            v[u] = True

            for uv, ud in self.e[u]:
                if v[uv]:
                    continue
                vd = k + ud
                if d[uv] > vd:
                    d[uv] = vd
                    heapq.heappush(q, (vd, uv))

        return d

N,M,P = map(int, input().split())
S,G = map(int, input().split())
D = Dijkstra()
for _ in range(M):
    a,b = map(int, input().split())
    D.add(a,-b,1)
    D.add(-a,b,1)
SD = D.search(S)
if P%2==1:
    G=-G
GD = D.search(G)
dis = SD[G]
if dis==float('inf'):
    print(-1)
    exit()
amari = (P-dis)//2
ANS = []
for i in range(1,N+1):
    if (SD[i]+GD[i]<=P and (SD[i]+GD[i])%2==P%2) or \
        (SD[i]+GD[-i]<=P and (SD[i]+GD[-i])%2==P%2) or \
        (SD[-i]+GD[i]<=P and (SD[-i]+GD[i])%2==P%2) or \
        (SD[-i]+GD[-i]<=P and (SD[-i]+GD[-i])%2==P%2) or \
        SD[i]<=amari or SD[-i]<=amari or GD[i]<=amari or GD[-i]<=amari:
        ANS.append(i)
print(len(ANS))
for ans in ANS:
    print(ans)