import sys
input = sys.stdin.readline
from collections import deque

N,M,P=map(int,input().split())
S,G=map(int,input().split())
E=[[] for i in range(N+1)]

for i in range(M):
    x,y=map(int,input().split())
    E[x].append(y)
    E[y].append(x)

SE=[1<<50]*(N+1)
SO=[1<<50]*(N+1)
GE=[1<<50]*(N+1)
GO=[1<<50]*(N+1)

SE[S]=0
GE[G]=0

Q=deque([S])

while Q:
    x=Q.popleft()
    for to in E[x]:
        if SE[x]<1<<50 and SO[to]>SE[x]+1:
            SO[to]=SE[x]+1
            Q.append(to)
        if SO[x]<1<<50 and SE[to]>SO[x]+1:
            SE[to]=SO[x]+1
            Q.append(to)

Q=deque([G])

while Q:
    x=Q.popleft()
    for to in E[x]:
        if GE[x]<1<<50 and GO[to]>GE[x]+1:
            GO[to]=GE[x]+1
            Q.append(to)
        if GO[x]<1<<50 and GE[to]>GO[x]+1:
            GE[to]=GO[x]+1
            Q.append(to)

ANS=[]
for i in range(1,N+1):
    if P%2==0:
        if SE[i]+GE[i]<=P:
            ANS.append(i)
        elif SO[i]+GO[i]<=P:
            ANS.append(i)
    else:
        if SE[i]+GO[i]<=P:
            ANS.append(i)
        elif SO[i]+GE[i]<=P:
            ANS.append(i)

ANS.sort()
if len(ANS)==0:
    print(-1)
else:
    print(len(ANS))
    print("\n".join(map(str,ANS)))