#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,popcnt,sse4")
#define ll long long
#define pll pair<ll,ll>
#define pii pair<int,int>
#define fs first
#define sc second
#define tlll tuple<ll,ll,ll>
const int mxn = 5e4+10;
vector<int> paths[mxn];
int sz[mxn];
int N,K;
inline bool check(vector<int> &tar){
sort(tar.begin(),tar.end());
for(auto &i:tar){
int pre = 0;
for(auto &j:tar){
if(j == i)continue;
auto it = lower_bound(paths[i].begin()+pre,paths[i].end(),j)-paths[i].begin();
if(it == sz[i]||paths[i][it] != j)return false;
pre = it;
}
}
return true;
}
int main(){
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>N>>K;
for(int i = 0;i<N;i++){
int c;
cin>>c;
sz[i] = c;
while(c--){
int tmp;
cin>>tmp;
paths[i].push_back(tmp);
}
sort(paths[i].begin(),paths[i].end());
}
int ans = 0;
for(int i = 0;i<N;i++){
if(sz[i]>K)continue;
for(int j =0;j<(1<<sz[i]);j++){
vector<int> tar;
tar.push_back(i);
for(int l = 0;l<sz[i];l++){
if(j&(1<<l))tar.push_back(paths[i][l]);
}
if(check(tar))ans = max(ans,__builtin_popcount(j)+1);
}
}
cout<<ans;
}
