#include <iostream>
#include <fstream>
#include <utility>
#include <algorithm>
#define DEBUG 1

using namespace std;

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

int n, t;
pair<int, pair<int, int>> v[4001];
int tree[4001][4001];

void update(int x, int y, int val)
{
    for(int i = x; i <= n; i += i&-i)
        for(int j = y; j <= n; j += j&-j)
            tree[i][j] = max(val, tree[i][j]);
}

int query(int x, int y)
{
    int s = 0;

    for(int i = x; i; i -= i&-i)
        for(int j = y; j; j -= j&-j)
            s = max(s, tree[i][j]);

    return s;
}

void wipe(int x, int y)
{
    for(int i = x; i <= n; i+= i&-i)
        for(int j = y; j <= n; j += j&-j)
            tree[i][j] = 0;
}

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

    while(t--)
    {
        for(int i = 1; i <= n; i++)
            in >> v[i].first >> v[i].second.first >> v[i].second.second;

        sort(v+1, v+n+1);

        for(int i = 1; i <= n; i++)
        {
            int rez = query(v[i].second.first-1, v[i].second.second-1);
            update(v[i].second.first, v[i].second.second, rez+1);
        }

        out << query(n, n) << '\n';

        for(int i = 1; i <= n; i++)
            wipe(v[i].second.first, v[i].second.second);
    }

    return 0;
}