#include <fstream>
#include <vector>
#include <algorithm>

#define LSOne(x) (x & (-x))

using namespace std;

ifstream cin("cutii.in");
ofstream cout("cutii.out");

int n, t, x, y, z;

int aib[3505][3505];

struct cutie
{
    int x, y, z;
};

bool cmp(cutie c1, cutie c2)
{
    return c1.z < c2.z;
}
vector<cutie> cutii;

void u(int x, int y, int val)
{
    for (int i = x; i <= n; i += LSOne(i))
        for (int j = y; j <= n; j += LSOne(j))
            aib[i][j] = max(val, aib[i][j]);
}

int q(int x, int y)
{
    int sum = 0;
    for (int i = x; i > 0; i -= LSOne(i))
        for (int j = y; j > 0; j -= LSOne(j))
            sum = max(sum, aib[i][j]);
    return sum;
}

void c(int x, int y)
{
    for (int i = x; i <= n; i += LSOne(i))
        for (int j = y; j <= n; j += LSOne(j))
            aib[i][j] = 0;
}

void solve()
{
    cutii.clear();
    for (int i = 1; i <= n; ++i)
    {
        cin >> x >> y >> z;
        cutii.push_back({ x, y, z });
    }
    sort(cutii.begin(), cutii.end(), cmp);
    int best;
    for (auto it : cutii)
    {
        best = q(it.x, it.y) + 1;
        u(it.x, it.y, best);
    }


    cout << q(n, n) << '\n';
    for (auto it : cutii)
        c(it.x, it.y);

}

int main()
{
    cin >> n >> t;

    while(t--)
        solve();

    return 0;
}