#include <fstream>
#include <algorithm>
#define DIM 3502

using namespace std;

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

int n, T, res, aib[DIM][DIM];

struct cutie{
    int x, y, z;
}c[DIM];

bool cmp(cutie a, cutie b){
    return a.z < b.z;
}

int query(int ii, int jj){
    int s = 0;
    for(int i = ii ; i; i -= (i & -i))
        for(int j = jj ; j; j -= (j & -j))
            s = max(s, aib[i][j]);
    return s;
}

void update(int ii, int jj, int val){
    for(int i = ii; i <= n; i += (i & -i))
        for(int j = jj; j <= n; j += (j & -j))
            aib[i][j] = max(aib[i][j], val);
}

void curata(int ii, int jj){
    for(int i = ii; i <= n; i += (i & -i))
        for(int j = jj; j <= n; j += (j & -j))
            aib[i][j] = 0;
}

int main()
{
    f>>n>>T;
    for(int t = 1; t <= T; ++ t){
        for(int i = 1; i <= n; ++ i)
            f>>c[i].x>>c[i].y>>c[i].z;
        sort(c + 1, c + n + 1, cmp);
        for(int i = 1; i <= n; ++ i){
            int rez = query(c[i].x - 1, c[i].y - 1);
            update(c[i].x, c[i].y, rez + 1);
        }
        g<<query(n, n)<<'\n';
        for(int i = 1; i <= n; ++ i){
            curata(c[i].x, c[i].y);
        }
    }

    return 0;
}