n = int(input())

def query(X):
    X = list(X)
    X.sort()
    print('?', len(X), flush=True)
    print(*X, flush=True)

A = set(range(1, n+1))
NG = set()
for i in range(1, n+1):
    A.remove(i)
    query(A)
    ans = int(input())
    if ans == 1:
        NG.add(i)
    A.add(i)
ANS = []
for i in range(1, n+1):
    if i not in NG:
        ANS.append(i)
print('!', len(ANS), flush=True)
print(*ANS)