N, M = map(int, input().split())
A = list(map(int, input().split()))

dp = [[False] * (M + 1) for _ in range(N + 1)]
dp[N][0] = True
for i in range(N-1, -1, -1):
    for j in range(M + 1):
        dp[i][j] = dp[i + 1][j]
    for j in range(A[i], M + 1):
        dp[i][j] = dp[i][j] or dp[i + 1][j - A[i]]

if not dp[0][M]:
    print(-1)
    exit()

L = list(map(int, input().split()))
P = [0] * N
for i in range(N):
    P[L[i] - 1] = i

now = M
ans = [-1]

while now != 0:
    for i in range(N):
        if ans[-1] > P[i]:
            continue
        if now >= A[P[i]] and dp[P[i]][now] and dp[P[i] + 1][now - A[P[i]]]:
            ans += [P[i] + 1]
            now -= A[P[i]]
            break

print(len(ans) - 1)
print(*ans[1:])