#include<iostream>

#include<stdio.h>

#include<cmath>

#include<string>

#include<queue>

#include<set>

#include<vector>

#include<string.h>

#include<algorithm>

typedef long long int ll;

using namespace std;

const int maxn = 1e5 + ;

const int inf = 0x3f3f3f3f;

const ll mod = 1e9 + ;

vector<int> G[maxn];

struct node{

    int id, sz, num;

};

struct compare{

    bool operator () (node a, node b){

        return a.sz > b.sz;

    }

};

node add(int id, int sz){

    node a;

    a.id = id , a.sz = sz, a.num = ;

    return a;

}

multiset<node, compare> q;

int main(){

    int T, a;

    scanf("%d", &T);

    while(T--){

        q.clear();

        int n;

        scanf("%d", &n);

        scanf("%d", &a);

        int cnt = ;

        q.insert(add(, a));

        G[].clear();

        G[].push_back();

        node p;

        for(int i = ; i <= n; i++){

            scanf("%d" ,&a);

            multiset<node>::iterator it;

            p.sz = a;

            it = q.lower_bound(p);

            if(it == q.end()){

                q.insert(add(cnt, a));

                G[cnt].clear();

                G[cnt].push_back(i);

                cnt++;

            }

            else{

                p = *it;

                q.erase(it);

                p.num++;

                if(p.num < )

                    q.insert(p);

                q.insert(add(p.id, a));

                G[p.id].push_back(i);

            }

        }

        printf("%d\n", cnt - );

        for(int i = ; i < cnt; i++){

            int len = G[i].size();

            printf("%d", len);

            for(int j = ; j < len; j++)

                printf(" %d", G[i][j]);

            printf("\n");

        }

    }

    return ;

}