#include<bits/stdc++.h>
#define st first
#define nd second
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define eb emplace_back
#define pp pop_back
#define mp make_pair
using namespace std;
using pii = pair<int, int>;
using ll = long long;
using vi = vector<int>;
using vii = vector<pii>;
using ld = long double;
void debug(){cerr<<"\n";}
template<typename H, typename... T>
void debug(H h, T... t){
cerr<<h;
if(sizeof...(t)){
cerr<<", ";
}
debug(t...);
}
#define deb(x...) cerr<<#x<<" = ";debug(x);
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const int N=3005;
vi par[N][N];
vector<bool> par2[N][N];
int opt[N], tim[N], ile[N], str[N][N];
int main(){
int n, m;
cin>>n;
vii V(n);
int M=0;
for(int i=0;i<n; i++){
cin>>V[i].st;
M=max(M, V[i].st);
for(int j=0; j<V[i].st; j++)ile[j]++;
V[i].nd=i+1;
}
sort(all(V));
int s=0;
for(int i=0; i<M; i++){
for(int j=s; j<s+ile[M-i-1]; j++){
tim[j]=i;
}
s+=ile[M-i-1];
}
tim[s]=M;
for(int i=1; i<=s; i++){
opt[i]=-1e9;
//deb(i, tim[i]);
}
cin>>m;
vi V2(m);
for(int &i:V2){
cin>>i;
}
sort(all(V2));
for(int i=0; i<=s; i++){
for(int j=0; j<=M; j++){
str[i][j]=1e9;
}
}
str[0][0]=0;
opt[0]=0;
int C=100;
for(int c:V2){
for(int i=c; i<=s; i++){
if(opt[i]<min(opt[i-c]+1, tim[i])){
opt[i]=min(opt[i-c]+1, tim[i]);
}
for(int j=max(1, opt[i]-C); j<=opt[i]; j++){
if(str[i][j]>str[i-c][j-1]){
str[i][j]=str[i-c][j-1];
par[i][j].pb(c);
par2[i][j].pb(0);
}
}
for(int j=max(0, opt[i]-C); j<=opt[i]; j++){
if(str[i][j]>str[i-c][j]+1){
str[i][j]=str[i-c][j]+1;
par[i][j].pb(c);
par2[i][j].pb(1);
}
}
}
//for(int i=0; i<=s; i++){deb(i, tim[i], opt[i]);}
/*cout<<c<<"\n";
for(int i=0; i<=s; i++){
deb(i, opt[i], tim[i]);
for(int j=0; j<=opt[i]; j++){
cout<<str[i][j]<<" ";
}
cout<<"\n";
}*/
}
if(opt[s]!=M){
cout<<-1;
return 0;
}
vi siz;
int prv=1e9;
int j=M;
while(s){
//deb(s,j,str[s][j]);
//deb(par[s][j].size());
while(par[s][j].back()>prv){
par[s][j].pp();
par2[s][j].pp();
}
int jj=par2[s][j].back();
prv=par[s][j].back();
//deb(prv, jj);
siz.pb(prv);
s-=prv;
j-=1-jj;
}
cout<<siz.size()<<"\n";
//for(int i:siz)cout<<i<<" ";
//return 0;
priority_queue<pair<int, int> > Q;
for(auto &i:V)Q.push(i);
for(int j:siz){
cout<<j<<" ";
vii todo;
for(int i=0; i<j; i++){
assert(Q.size());
todo.pb(Q.top());
Q.pop();
cout<<todo.back().nd<<" ";
todo.back().st--;
}
cout<<"\n";
for(auto i:todo){
if(i.st)Q.push(i);
}
}
}
