#include <iostream>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <random>
#include <stdio.h>
#include <fstream>
#include <functional>
#include <cassert>
#include "testlib.h"
using namespace std;

#define rep(i,n,c) for (int i=0;i<n;i+=c)
#define append push_back
#define all(x) (x).begin(), (x).end()

template<class T>
using vec = vector<T>;
template<class T>
using vvec = vec<vec<T>>;
template<class T>
using vvvec = vec<vvec<T>>;
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;


template<class T>
bool chmin(T &a, T b){
  if (a>b){
    a = b;
    return true;
  }
  return false;
}

template<class T>
bool chmax(T &a, T b){
  if (a<b){
    a = b;
    return true;
  }
  return false;
}

template<class T>
T sum(vec<T> x){
  T res=0;
  for (auto e:x){
    res += e;
  }
  return res;
}

template<class T>
void printv(vec<T> x){
  for (auto e:x){
    cout<<e<<" ";
  }
  cout<<"\n";
}

const int M = 1000000;

int spf[M+1];

void calc_spf(){
  spf[1] = 1;
  for (int i=2;i<M+1;i++){
    if (spf[i]==0){
      spf[i] = i;
      for (int j=2*i;j<M+1;j+=i){
        spf[j] = i;
      }
    }
  }
}

int pow(int n,int k){
  int res = 1;
  while(k){
    if (k&1){
      res *= n;
    }
    n *= n;
    k >>= 1;
  }
  return res;
}

map<int,int> factorization(int n){
  assert (1 <= n);
  assert (n <= M);
  map<int,int> res;
  int p,cnt;
  while (n!=1){
    p = spf[n];
    cnt = 0;
    while (n%p==0){
      cnt += 1;
      n /= p;
    }
    res[p] = cnt;
  }
  return res;
}

const int MIN_N = 1;
const int MAX_N = 1000000;

int main(int argc, char* argv[]){
  registerValidation(argc,argv);
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);

  calc_spf();

  map<int,int> all_prime;
  
  int N;
  N = inf.readInt(MIN_N,MAX_N);
  inf.readEoln();
  vec<int> A(N,0);
  vec<int> C(M+1,0);
  set<int> check;
  for (int i=0;i<N;i++){
    A[i] = inf.readInt(1,M);
    C[A[i]] += 1;
    check.insert(A[i]);
    auto a_prime = factorization(A[i]);
    for(auto [p,cnt]:a_prime){
      all_prime[p];
      chmax(all_prime[p],cnt);
    }
    if (i!=N-1){
      inf.readSpace();
    }
    else{
      inf.readEoln();
    }
  }

  assert (check.size()==N);
  inf.readEof();

  for (int i=1;i<M+1;i++){
    for (int j=2*i;j<M+1;j+=i){
      C[i] += C[j];
    }
  }

  vec<int> P(0);
  for (auto [p,cnt]:all_prime){
    P.append(pow(p,cnt));
  }
  int n = P.size();

  sort(all(P));
  deque<pll> deq;
  deq.append({1ll,-1});
  ll break_point = -1;
  while (!deq.empty()){
    auto [v,k] = deq.front();
    deq.pop_front();
    for (int i=k+1;i<n;i++){
      if (v * (ll)(P[i]) > M){
        break_point = v * (ll)(P[i]);
        deq = {};
        break;
      }
      if (C[v*P[i]]==0){
        break_point = v * (ll)(P[i]);
        deq = {};
        break;
      }
      deq.append({v*P[i],i});
    }
  }

  if (break_point==-1){
    cout<<-1<<endl;
    return 0;
  }

  vec<int> select_P={};
  for (int i=0;i<n;i++){
    if (break_point%P[i]==0){
      select_P.append(P[i]);
    }
  }

  int k = select_P.size();
  vec<vec<int>> S(k,vec<int>(0));
  for (auto a:A){
    for (int i=0;i<k;i++){
      if (a%select_P[i]!=0){
        S[i].append(a);
        break;
      }
    }
  }
  
  cout<<k<<endl;
  for (int i=0;i<k;i++){
    cout<<S[i].size()<<" ";
    printv(S[i]);
  }



}