import heapq
import queue
inf = 3 * (10 ** 18)
n, m, p = map(int, input().split())
s, g = map(int, input().split())
road = [[0 for j in range(0)] for i in range(n + 1)]
kyo_s = [[inf for j in range(2)] for i in range(n + 1)]
kyo_g = [[inf for j in range(2)] for i in range(n + 1)]
kyo_s[s][0] = 0
kyo_g[g][0] = 0
ans = []
for _ in range(m):
    u, v = map(int, input().split())
    road[u].append(v)
    road[v].append(u)

q = queue.Queue()
q.put([0, s])
while q.empty() == False:
    k = q.get()
    cnt = k[0]
    x = k[1]
    if kyo_s[x][cnt % 2] < cnt:
        continue
    cnt += 1
    for i in road[x]:
        if kyo_s[i][cnt % 2] > cnt:
            q.put([cnt, i])
            kyo_s[i][cnt % 2] = cnt

q.put([0, g])
while q.empty() == False:
    k = q.get()
    cnt = k[0]
    x = k[1]
    if kyo_g[x][cnt % 2] < cnt:
        continue
    cnt += 1
    for i in road[x]:
        if kyo_g[i][cnt % 2] > cnt:
            q.put([cnt, i])
            kyo_g[i][cnt % 2] = cnt

for i in range(1, n+1):
    if p % 2:
        odd = min(kyo_s[i][0] + kyo_g[i][1], kyo_s[i][1] + kyo_g[i][0])
        if odd <= p:
            ans.append(i)
    else:
        even = min(kyo_s[i][0] + kyo_g[i][0], kyo_s[i][1] + kyo_g[i][1])
        if even <= p:
            ans.append(i)

if (len(ans) == 0):
    print(-1)
else:
    print(len(ans))
    for i in ans:
        print(i)