N, M = map(int, input().split())
S, G = map(lambda x: int(x) - 1, input().split())

graph = [[] for _ in range(N)]

for _ in range(M):
    f, t = map(lambda x: int(x) - 1, input().split())
    graph[f].append(t)
    graph[t].append(f)

input()
dont_use = set(map(lambda x: int(x) - 1, input().split()))

que = [S]
visited = [False] * N
visited[S] = True
while que:
    v = que.pop()
    for nx in graph[v]:
        if visited[nx]:
            continue
        if nx in dont_use:
            continue
        visited[nx] = True
        que.append(nx)
print("YNeos"[1 ^ visited[G] :: 2])