N,M = map(int,input().split())
S,G = map(int,input().split())
F = [0] * M
T = [0] * M
for i in range(M):
    F[i],T[i] = map(int,input().split())
U = int(input())
I = list(map(int,input().split()))
s = set(I)
graph = [[] for _ in range(N+1)]
for i in range(M):
    if F[i] not in s and T[i] not in s:
        graph[F[i]].append(T[i])
        graph[T[i]].append(F[i])
stack = [S]
memo = [0] * (N+1)
memo[S] = 1
while stack:
    now = stack.pop()
    for v in graph[now]:
        if memo[v] == 0:
            memo[v] = 1
            stack.append(v)
if memo[G] == 0:
    print('No')
else:
    print('Yes')