/*
* Author: Xiangmy
* Created: 2024-03-22 16:47
* Problem: 
* Description: 
*/
// #pragma GCC optimize(2)
// #pragma GCC optimize(3, "Ofast", "inline")
#include<bits/stdc++.h>
using namespace std;
#define debug(x) cerr << #x << ": " << (x) << ' '
// #define x first
// #define y second
typedef long long LL;
const int INF = 0x3f3f3f3f;
typedef pair<int, int> PII;

void solve() {
    int n; cin >> n;
    vector<int> a(n + 1);
    map<int, vector<int>> mp;
    for (int i = 1; i <= n; ++ i) cin >> a[i];

    mp[a[1]].push_back(1);
    set<int> st; st.insert(a[1]);
    for (int i = 2; i <= n; ++ i) {
        auto x = st.upper_bound(a[i]);
        if (x == st.begin()) {
            mp[a[i]].push_back(i);
            st.insert(a[i]);
        } else {
            -- x;
            mp[*x].push_back(i);
        }
    }

    cout << mp.size() << "\n";
    for (int i = 1; i <= n; ++ i) {
        if (mp.count(i)) {
            cout << mp[i].size();
            for (auto x : mp[i]) {
                cout << ' ' << x;
            }
            cout << "\n";
        }
    }
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);  // 交互题不用
    cout.tie(0);
    // cout << fixed << setprecision(6);
    // cout << setw(4) << setfill('0');
    // init();
    int T = 1;
    cin >> T;
    while (T -- ) {
        // cin.ignore(numeric_limits<std::streamsize>::max(), '\n');
        solve();
    }
    return 0;
}