#include <bits/stdc++.h>
#define zeros(x) (x & (-x))

using namespace std;
ifstream f("cutii.in");
ofstream g("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 update(int x, int y, int val)
{
    for (int i = x; i <= n; i += zeros(i))
        for (int j = y; j <= n; j += zeros(j))
            aib[i][j] = max(val, aib[i][j]);
}

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

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

void Solve()
{
    cutii.clear();
    for (int i = 1; i <= n; ++i)
    {
        f >> x >> y >> z;
        cutii.push_back({ x, y, z });
    }
    sort(cutii.begin(), cutii.end(), cmp);
    int best;
    for (auto it : cutii)
    {
        best = query(it.x, it.y) + 1;
        update(it.x, it.y, best);
    }
    g << query(n, n) << '\n';
    for (auto it : cutii)
        clear(it.x, it.y);
}

void Read()
{
    f >> n >> t;
    for (int i = 1; i <= t; ++i)
        Solve();
}

int main()
{
    Read();
    return 0;
}