#include <fstream>
using namespace std;
const string file = "cutii"; const string infile = file + ".in"; const string outfile = file + ".out";
struct Cutie
{short x;short y;short z;
	Cutie(short x = 0, short y = 0, short z = 0)
    {
        this->x = x; this->y = y; this->z = z;
    }
 
    bool operator < (const Cutie& other) const
    {
        return this->z < other.z;
    }
};
 
const int MAXN = 3505;
Cutie cutii[MAXN];
short _data[MAXN][MAXN];
 
class Aib2DMax
{
public:
    static short zeros(short x);
    Aib2DMax(const short maxI, const short maxJ);
    void Reset(const short i, const short j); void Update(const short i, const short j, const short val);
    short Query(const short i, const short j);
protected:
private:
    short _maxI;short _maxJ;
};
 
inline short Aib2DMax::zeros(short x)
{
    return (x ^ (x - 1)) & x;
}
 
 
Aib2DMax::Aib2DMax(const short maxI, const short maxJ)
{
    this->_maxI = maxI;
    this->_maxJ = maxJ;
}
 
inline void Aib2DMax::Reset(const short i, const short j)
{
    for(short x = i; x <= _maxI; x += zeros(x))
    {
        for(short y = j; y <= _maxJ; y += zeros(y))
        {
            _data[x][y] = 0;
        }
    }
}
 
inline void Aib2DMax::Update(const short i, const short j, const short value)
{
    for(short x = i; x <= _maxI; x += zeros(x))
    {
        for(short y = j; y <= _maxJ; y += zeros(y))
        {
            _data[x][y] = max(_data[x][y], value);
        }
    }
}
 
inline short Aib2DMax::Query(const short i, const short j)
{
    short maxi = 0;
    for(short x = i; x > 0; x -= zeros(x))
    {
        for(short y = j; y > 0; y -= zeros(y))
        {
            maxi = max(maxi, _data[x][y]);
        }
    }
    return maxi;
}
 
int main()
{
    short N, T;
    fstream fout(outfile.c_str(), ios::out); fstream fin(infile.c_str(), ios::in);
    fin >> N >> T;
 
    Aib2DMax aib(N, N);
 
    for(short i = 0; i < T; i++)
    {
        for(short j = 1; j <= N; j++)
        {
            fin >> cutii[j].x >> cutii[j].y >> cutii[j].z;
 
        }
 
        short sol = 0;
        sort(cutii + 1, cutii + N + 1);
         
 
        for(short i = 1; i <= N; i++)
        {
            short c = aib.Query(cutii[i].x - 1, cutii[i].y - 1) + 1;
            aib.Update(cutii[i].x, cutii[i].y, c);
            sol = max(sol, c);
        }
 
        for(short i = 1; i <= N; i++)
        {
            aib.Reset(cutii[i].x, cutii[i].y);
        }
        fout << sol << "\n";
    }
 
    fin.close();
    fout.close();
}