mod = 998244353
eps = 10**-9


def main():
    import sys
    input = sys.stdin.buffer.readline

    N, M = map(int, input().split())
    A = list(map(int, input().split()))
    adj = [[] for _ in range(N+1)]
    for _ in range(M):
        a, b = map(int, input().split())
        adj[a].append(b)
        adj[b].append(a)
    K = int(input())
    B = list(map(int, input().split()))

    AI = [(a, i+1) for i, a in enumerate(A)]
    AI.sort(key=lambda x: x[0])
    on = [0] * (N+1)
    for b in B:
        on[b] = 1
    ans = []
    for a, i in AI:
        if on[i]:
            ans.append(i)
            on[i] = 0
            for j in adj[i]:
                if A[i-1] < A[j-1]:
                    on[j] ^= 1
    print(len(ans))
    print(*ans, sep="\n")


if __name__ == '__main__':
    main()