#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#define FOR(i,a) for (int i=0;i<(a);++i)
#define FORD(i,a) for (int i=(a)-1;i>=0;i--)
#define FORT(i,a,b) for (int i=(a);i<=(b);++i)
#define FORTD(i,b,a) for (int i=(b);i>=(a);--i)
#define trav(i,v) for (auto i : v)
#define all(v) v.begin(),v.end()
#define ad push_back
#define fr first
#define sc second
#define mpr(a,b) make_pair(a,b)
#define pir pair<int,int>
#define all(v) v.begin(),v.end()
#define make_unique(v) v.erase(unique(all(v)),v.end())
#define fastio ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define srng mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define y1 EsiHancagorcRepa
const int N=1e5+10;
const ll MOD=1e9+7;
int n,deg[N],vrj[N],ppc[N];
vector<int> g[N];
map<int,bool> mp[N];
priority_queue<pir> pq;
int kp[N],ans=1;
bool pat[N];
void solve(int k){
vector<int> v;
trav(to,g[k]){
if (deg[to])v.ad(to);
}
FOR(i,v.size()){
FOR(j,v.size()){
if (mp[v[i]][v[j]])kp[i]+=(1<<j);
}
}
//cout<<1<<endl;
//cout<<k<<endl;
pat[0]=true;
FORT(msk,1,(1<<v.size())-1){
int tv=msk-(1<<vrj[msk]);
//cout<<msk<<" "<<tv<<" "<<vrj[msk]<<" "<<kp[vrj[msk]]<<" "<<pat[tv]<<" "<<(kp[vrj[msk]]&tv)<<endl;
if (pat[tv] && ((kp[vrj[msk]]&tv)==tv)){
//cout<<"yoohoo"<<endl;
pat[msk]=true;
ans=max(ans,ppc[msk]+1);
}
else{
pat[msk]=false;
}
}
FOR(i,v.size()){
kp[i]=0;
deg[v[i]]--;
pq.push({-deg[v[i]],v[i]});
}
deg[k]=0;
}
int main(){
fastio;
srng;
FOR(msk,(1<<10)){
FOR(i,10){
if (msk&(1<<i)){
vrj[msk]=i;
ppc[msk]++;
}
}
}
int k;
cin>>n>>k;
FOR(i,n){
int d;
cin>>d;
deg[i]=d;
pq.push({-d,i});
FOR(j,d){
int to;
cin>>to;
g[i].ad(to);
mp[i][to]=true;
}
}
while(!pq.empty()){
int v,dg;
do{
v=pq.top().sc;
//cout<<v<<endl;
dg=-pq.top().fr;
pq.pop();
}while(!pq.empty() && deg[v]!=dg);
if (pq.empty())break;
//cout<<1<<endl;
solve(v);
}
cout<<ans<<endl;
return 0;
}
