import sys
readline = sys.stdin.readline


N, M = map(int, readline().split())
A = list(map(int, readline().split()))
G = [[] for i in range(N)]
for i in range(M):
    u, v = map(int, readline().split())
    u, v = u - 1, v - 1
    G[u].append(v)
    G[v].append(u)
    
D = [None] * N
for i in range(N):
    D[i] = (A[i], i)
D.sort()

K = int(readline())
B = list(map(int, readline().split()))
lamp = [0] * N
for b in B:
    lamp[b - 1] = 1
    
ans = []
for a, i in D:
    if lamp[i] == 0:
        continue
    ans.append(i + 1)
    for u in G[i]:
        if A[u] > a:
            lamp[u] = 1 - lamp[u]

print(len(ans))
for a in ans:
    print(a)