M = 10**6
spf = [i for i in range(M+1)]
for i in range(2,M+1):
    if spf[i]==i:
        for j in range(2*i,M+1,i):
            spf[j] = i

def factorization(n):
    assert 1<=n<=10**6
    res = {}
    while n!=1:
        p = spf[n]
        res[p] = 0
        while n%p==0:
            res[p] += 1
            n //= p
    return res

from collections import deque

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

pre = [0 for i in range(M+1)]
cnt = [0 for i in range(M+1)]
for a in A:
    prime = factorization(a)
    for p in prime:
        pre[p] = max(pre[p],pow(p,prime[p]))
    cnt[a] += 1

P = [val for val in pre if val!=0]
for i in range(1,M+1):
    for j in range(2*i,M+1,i):
        cnt[i] += cnt[j]
n = len(P)

deq = deque([(1,-1)])
break_point = -1
while deq:
    v,k = deq.popleft()
    for i in range(k+1,n):
        if M < v * P[i]:
            break_point = v * P[i]
            deq = []
            break
        if not cnt[v*P[i]]:
            break_point = v * P[i]
            deq = []
            break
        deq.append((v*P[i],i))

if break_point==-1:
    exit(print(-1))

k = 0
p = []
for i in range(n):
    if break_point%P[i]==0:
        p.append(P[i])
        k += 1

S = [[] for i in range(k)]
for a in A:
    for i in range(k):
        if a%p[i]:
            S[i].append(a)
            break
print(k)
for i in range(k):
    S[i] = [len(S[i])] + S[i]
    print(*S[i])