#include <bits/stdc++.h>
#define lim 3502

using namespace std;
ifstream fin("cutii.in");
ofstream fout("cutii.out");

short t,n;
short aib[lim][lim],verif[lim][lim];
short x, y, z;
pair<short,short> c[lim];

short cutie(short actualX,short actualY)
{
    short cut=0;
    for(short i=actualX; i>0; i-=(i)&(-i))
        for(short j=actualY; j>0; j-=(j)&(-j))
        {
            if(verif[i][j]!=t)aib[i][j]=0;
            cut=max(cut,aib[i][j]);
            verif[i][j]=t;
        }
    return cut;
}

void update(short actualX,short actualY)
{
    for(short i=actualX; i<=n; i+=(i)&(-i))
        for(short j=actualY; j<=n;j+=(j)&(-j))
        {
            if(verif[i][j]!=t)
                aib[i][j]=0;
            aib[i][j]=max(aib[i][j],aib[actualX][actualY]);
            verif[i][j]=t;
        }
}


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

    while(t)
    {
        for(short i=1; i<=n; i++)
        {
            fin>>x>>y>>z;
            c[z].first=x;
            c[z].second=y;
        }
        short rez=0;
        for(short i=1; i<=n; i++)
        {
            short actualX,actualY;
            actualX=c[i].first;
            actualY=c[i].second;
            aib[actualX][actualY]=cutie(actualX-1,actualY-1)+1;
            verif[actualX][actualY]=t;
            update(actualX,actualY);
            rez=max(rez,aib[actualX][actualY]);
        }
        fout<<rez<<'\n';
        t--;
    }

    return 0;
}