#include <bits/stdc++.h>
#define rep(a,b,c) for(auto a = (b); a != (c); a++)
#define repD(a,b,c) for(auto a = (b); a != (c); a--)
#define repIn(a, b) for(auto& a : (b))
#define repIn2(a, b, c) for(auto& [a, b] : (c))
constexpr bool dbg = 1;
#define DEBUG if constexpr(dbg)
#define DC DEBUG std::cerr
#define eol std::endl
#define int long long
#define ld long double
#define pb push_back
#define rg ranges
using namespace std;
constexpr int inf = 1e9 + 7;
int32_t main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
int n;
cin >> n;
vector<int> v(n);
repIn(i, v) cin >> i;
vector<pair<int, int>> vp(n);
rep(i, 0, n) vp[i] = {v[i], i};
rg::sort(v);
rg::reverse(v);
rg::sort(vp);
rg::reverse(vp);
int m;
cin >> m;
vector<int> s(m);
repIn(i, s) cin >> i;
rg::reverse(s);
int sumV = 0;
repIn(i, v) sumV += i;
vector<int> dp(sumV + 1, inf);
vector<int> dpFrom(sumV + 1, inf);
dp[0] = 0;
repIn(ms, s) {
vector<int> v2(n);
rep(i, 0, n) v2[i] = v[i];
int it = n - 1;
v2[it]++;
rep(i, 0, sumV - ms + 1) {
v2[it++]--;
if(it == n || !v2[it]) it = 0;
if(dp[i + ms] <= dp[i] + 1) continue;
int avail = 0;
rep(j, 0, n) avail += v2[j] > 0;
if(avail >= ms) dp[i + ms] = dp[i] + 1, dpFrom[i + ms] = ms;
}
}
cout << (dp.back() == inf ? -1 : dp.back()) << '\n';
if(dp.back() == inf) return 0;
vector<int> used;
int cur = sumV;
while(cur) used.pb(dpFrom[cur]), cur -= used.back();
rg::sort(used);
rg::reverse(used);
int it = 0;
repIn(ms, used) {
cout << ms << ' ';
rep(_, 0, ms) {
cout << vp[it].second + 1 << ' ';
vp[it++].first--;
if(it == n || !vp[it].first) it = 0;
}
cout << '\n';
}
}
