#include <algorithm>
#include <fstream>

using namespace std;

const int DIM = 3510;
ifstream fin("cutii.in");
ofstream fout("cutii.out");
struct box
{
    int x, y, z;
    box()
    {
        x = y = z = 0;
    }
    box(int x, int y, int z)
    {
        this->x = x;
        this->y = y;
        this->z = z;
    }
    inline bool operator < (const box &other) const
    {
        if (this->x == other.x)
        {
            if (this->y == other.y)
                return this->z < other.z;
            return this->y < other.y;
        }
        return this->x < other.x;
    }
};

box v[DIM];
int aib2d[DIM][DIM];
int dp[DIM];
int n, t;

inline int lsb(int x)
{
    return x & (-x);
}

void Update(int x, int y, int val)
{
    for (int i = x;i <= n;i += lsb(i))
        for (int j = y;j <= n;j += lsb(j))
            if (val != 0)
                aib2d[i][j] = max(aib2d[i][j], val);
            else
                aib2d[i][j] = 0;
}

int Query(int x, int y)
{
    int ret = 0;
    for (int i = x;i >= 1;i -= lsb(i))
        for (int j = y;j >= 1;j -= lsb(j))
            ret = max(ret, aib2d[i][j]);
    return ret;
}

void Solve()
{
    int ans = -1;
    for (int i = 1;i <= n;++i)
    {
        dp[i] = 1 + Query(v[i].y - 1, v[i].z - 1);
        Update(v[i].y, v[i].z, dp[i]);
        ans = max(ans, dp[i]);
    }
    for (int i = 1;i <= n;++i)
        Update(v[i].y, v[i].z, 0);
    fout << ans << "\n";
}

int main()
{
    fin >> n >> t;
    int x, y, z;
    for (int i = 1;i <= t;++i)
    {
        for (int j = 1;j <= n;++j)
        {
            fin >> x >> y >> z;
            v[j] = box(x, y, z);
        }
        sort(v + 1, v + n + 1);
        Solve();
    }
    fin.close();
    fout.close();
    return 0;
}