#pragma optimize("Bismillahirrahmanirrahim")
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
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//ahmet23 orz...
//FatihSultanMehmedHan
//YavuzSultanSelimHan
//AbdulhamidHan
//Sani buyuk Osman Pasa Plevneden cikmam diyor
#define author tolbi
#include <bits/stdc++.h>
using namespace std;
template<typename X, typename Y> istream& operator>>(istream& is, pair<X,Y> &pr){return is>>pr.first>>pr.second;}
#ifdef tolbi
template<typename X, typename Y> ostream& operator<<(ostream& os, pair<X,Y> pr){return os<<"{ "<<pr.first<<", "<<pr.second<<" }";}
#else
template<typename X, typename Y> ostream& operator<<(ostream& os, pair<X,Y> pr){return os<<pr.first<<" "<<pr.second;}
#endif
ostream& operator<<(ostream& os, bool bl){return os<<(int32_t)bl;}
template<typename X> istream& operator>>(istream& is, vector<X> &arr){for (auto &it : arr) is>>it; return is;}
template<typename X, size_t Y> istream& operator>>(istream& is, array<X,Y> &arr){for (auto &it : arr) is>>it; return is;}
template<typename X> ostream& operator<<(ostream& os, vector<X> &arr){for (auto &it : arr) os<<" "<<it;os<<endl;return os;}
template<typename X, size_t Y> ostream& operator<<(ostream& os, array<X,Y> &arr){for (auto &it : arr) os<<" "<<it;os<<endl;return os;}
#define endl '\n'
#define deci(x) int x;cin>>x;
#define decstr(x) string x;cin>>x;
#define cinarr(x) for (auto &it : x) cin>>it;
#define coutarr(x) for(auto &it : x) cout<<it<<" ";cout<<endl;
#define sortarr(x) sort(x.begin(), x.end())
#define sortrarr(x) sort(x.rbegin(), x.rend())
#define rev(x) reverse(x.begin(), x.end())
#define tol(bi) (1LL<<((int)(bi)))
#define ios ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
const int MOD = 1e9+7;
mt19937 ayahya(chrono::high_resolution_clock().now().time_since_epoch().count());
int32_t main(){
ios;
int T = 1;
if (!T) cin>>T;
int tno = 0;
while (T-(tno++)){
bitset<50000> full;
deci(n);deci(k);
vector<vector<int>> gr(n);
vector<pair<int,int>> pr(n);
vector<bitset<50000>> arr(n);
for (int i = 0; i < n; ++i)
{
pr[i].second=i;
full[i]=1;
cin>>pr[i].first;
for (int j = 0; j < pr[i].first; j++){
deci(x);
gr[i].push_back(x);
}
}
sortarr(pr);
vector<int> pl(n);
for (int i = 0; i < n; ++i)
{
pl[pr[i].second]=i;
}
for (int i = 0; i < n; i++){
int node = pl[i];
for (int j = 0; j < gr[i].size(); j++){
int nex = pl[gr[i][j]];
arr[node][nex]=1;
}
}
bitset<50000> kk;
auto f = [&](bitset<50000> bs, int dept, auto f)->int{
if (dept==k) return 0;
int mava = 0;
if (bs.count()==0) return 0;
int pos = bs._Find_first();
while (pos<50000){
bs[pos]=0;
kk=bs&arr[pos];
mava=max(mava,f(kk,dept+1,f)+1);
pos=bs._Find_next(pos);
}
return mava;
};
cout<<f(full,0,f)<<endl;
}
}
