#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9;
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
int n, m;
cin >> n;
vector<int> a(n);
for (int &i : a) { cin >> i; }
cin >> m;
vector<int> b(m);
for (int &i : b) { cin >> i; }
vector<int> dp(n + 1, inf);
dp[0] = 0;
for (int i = 1; i <= n; ++i) {
for (int &s : b) {
if (i - s >= 0) {
dp[i] = min(dp[i], dp[i - s] + 1);
}
}
}
vector<int> ans;
int x = n;
while (x) {
for (int &s : b) {
if (x - s >= 0 && dp[x] == dp[x - s] + 1) {
ans.push_back(s);
x -= s;
break;
}
}
}
if (dp[n] == inf) {
cout << "-1\n";
return 0;
}
cout << dp[n] << '\n';
int p = 1;
for (int &i : ans) {
cout << i << ' ';
for (int j = 0; j < i; ++j) {
cout << p++ << ' ';
}
cout << '\n';
}
}
