n, m = map(int, input().split())
A = list(map(int, input().split()))
C = [(a, i) for i, a in enumerate(A)]
C.sort()
edges = [[] for _ in range(n)]
for _ in range(m):
    u, v = map(int, input().split())
    u -= 1
    v -= 1
    edges[u].append(v)
    edges[v].append(u)
k = int(input())
B = list(map(int, input().split()))
on = [True] * n
for b in B: on[b - 1] = False
ans = []
for a, i in C:
    if on[i]:
        continue
    ans.append(i + 1)
    on[i] ^= True
    for j in edges[i]:
        if a < A[j]:
            on[j] ^= True
            
assert all(o for o in on)

print(len(ans))
print(*ans, sep="\n")