using System;
using System.Linq;
using System.Numerics;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Timers;
using N = System.Int64;

static class Program
{
    static public void Main(string[] args)
    {
        Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
        var solver = new Solver();
        solver.Solve();
        Console.Out.Flush();
    }
}

public class Solver
{
    public void Solve()
    {
        int t = ri, r = ri;
        var uf = new UnionFind(5400);
        int p = 0;
        var s = new int[5400];
        for (int timer = 0; timer < t; timer++)
        {
            int n = ri;
            var ans = new List<string>();
            for (int i = 0; i < n; i++)
            {
                s[p + i] = ri;
                uf.SetData(p + i, s[p + i]);
            }
            if (timer > t * 5 / 100)
            {
                for (int i = 0; i < p + n; i++)
                {
                    if (uf.Size(i) > 1) continue;
                    for (int j = 0; j < i; j++)
                    {
                        if (uf.Size(j) < 4 && uf.GetNewValue(j, s[i], timer) - uf.GetNowValue(j) >= (t - 1 - timer))
                        {
                            uf.Unite(j, p + i, timer);
                            ans.Add($"{j + 1} {i + 1}");
                            break;
                        }
                    }
                }
            }
            if (ans.Count == 0) Write(0);
            else Write($"{ans.Count}\n{string.Join("\n", ans)}");
            Console.Out.Flush();
            p += n;
        }
    }
    public class UnionFind
    {
        private int _len;
        private int[] _par;
        private int[] _size;
        private int[] _skill_min;
        private int[] _skill_max;
        private int[] _tick_sum;
        private int[] _score_e;
        public UnionFind(int len)
        {
            _len = len;
            _par = new int[len];
            _size = new int[len];
            for (int i = 0; i < len; i++)
            {
                _par[i] = i;
                _size[i] = 1;
            }
            _skill_min = new int[len];
            _skill_max = new int[len];
            _tick_sum = new int[len];
            _score_e = new int[len];
        }
        public void SetData(int x, int s)
        {
            _skill_min[x] = s;
            _skill_max[x] = s;
        }
        public int GetNowValue(int x)
        {
            int rx = Root(x);
            int k = _size[rx] * (_size[rx] - 1) / 2;
            int skill = _skill_max[rx] - _skill_min[rx];
            return Math.Max(0, k * (200 - skill * skill) - _score_e[rx]);
        }
        public int GetNewValue(int x, int s, int t)
        {
            int rx = Root(x);
            int k = _size[rx] * (_size[rx] + 1) / 2;
            int skill = Math.Max(_skill_max[rx], s) - Math.Min(_skill_min[rx], s);
            return Math.Max(0, k * (200 - skill * skill) - (_score_e[rx] + _tick_sum[rx] - _size[rx] * t));
        }
        public int Root(int x)
        {
            if (_par[x] == x) return x;
            return _par[x] = Root(_par[x]);
        }
        public int Size(int x)
        {
            if (_par[x] == x) return _size[x];
            return _size[x] = _size[Root(x)];
        }
        public bool IsSame(int x, int y) { return Root(x) == Root(y); }
        public void Unite(int x, int y, int t)
        {
            int rx = Root(x);
            int ry = Root(y);
            if (rx != ry)
            {
                _score_e[rx] += _tick_sum[rx] - _size[rx] * t;
                _tick_sum[rx] += t;
                _par[ry] = rx;
                _size[rx] += _size[ry];
                _skill_max[rx] = Math.Max(_skill_max[rx], _skill_max[ry]);
                _skill_min[rx] = Math.Min(_skill_min[rx], _skill_min[ry]);
            }
        }
    }

    //int inf = 1 << 30;
    long inf = (long)1 << 60;
    int ri { get { return (int)sc.Integer(); } }
    long rl { get { return sc.Integer(); } }
    double rd { get { return sc.Double(); } }
    string rs { get { return sc.Scan(); } }
    public StreamScanner sc = new StreamScanner(Console.OpenStandardInput());

    void Write<T>(T t) { Console.WriteLine(t.ToString()); }
    void YN(bool t) { Console.WriteLine(t ? "YES" : "NO"); }
    void Yn(bool t) { Console.WriteLine(t ? "Yes" : "No"); }
    void yn(bool t) { Console.WriteLine(t ? "yes" : "no"); }
}



public class StreamScanner
{
    public StreamScanner(Stream stream) { str = stream; }
    private readonly Stream str;
    private readonly byte[] buf = new byte[1024];
    private int len, ptr;
    public bool isEof = false;
    public bool IsEndOfStream { get { return isEof; } }
    private byte read()
    {
        if (isEof) throw new EndOfStreamException();
        if (ptr >= len)
        {
            ptr = 0;
            if ((len = str.Read(buf, 0, 1024)) <= 0)
            {
                isEof = true;
                return 0;
            }
        }
        return buf[ptr++];
    }
    public char Char()
    {
        byte b = 0;
        do b = read();
        while (b < 33 || 126 < b);
        return (char)b;
    }
    public string Scan()
    {
        var sb = new StringBuilder();
        for (var b = Char(); b >= 33 && b <= 126; b = (char)read())
            sb.Append(b);
        return sb.ToString();
    }
    public long Integer()
    {
        long ret = 0; byte b = 0; var ng = false;
        do b = read();
        while (b != '-' && (b < '0' || '9' < b));
        if (b == '-') { ng = true; b = read(); }
        for (; true; b = read())
        {
            if (b < '0' || '9' < b)
                return ng ? -ret : ret;
            else ret = ret * 10 + b - '0';
        }
    }
    public double Double() { return double.Parse(Scan()); }
}