#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/trie_policy.hpp>
// #include <ext/rope>
using namespace std;
// using namespace __gnu_cxx;
// using namespace __gnu_pbds;
void Hollwo_Pelw();
signed main(){
#ifndef hollwo_pelw_local
if (fopen(".inp", "r"))
assert(freopen(".inp", "r", stdin)), assert(freopen(".out", "w", stdout));
#else
using namespace chrono;
auto start = steady_clock::now();
#endif
cin.tie(0), cout.tie(0) -> sync_with_stdio(0);
int testcases = 1;
// cin >> testcases;
for (int test = 1; test <= testcases; test++){
// cout << "Case #" << test << ": ";
Hollwo_Pelw();
}
#ifdef hollwo_pelw_local
auto end = steady_clock::now();
cout << "\nExecution time : " << duration_cast<milliseconds> (end - start).count() << "[ms]" << endl;
#endif
}
const int N = 5e4 + 5;
int n, k, con[10], dp[1 << 10], res;
set<int> adj[N];
void Hollwo_Pelw(){
cin >> n >> k;
set<pair<int, int>> pq;
for (int i = 0, j, d; i < n; i++) {
for (cin >> d; d --; )
cin >> j, adj[i].insert(j);
}
for (int i = 0; i < n; i++)
pq.emplace(adj[i].size(), i);
while (!pq.empty()) {
int u = pq.begin() -> second; pq.erase(pq.begin());
vector<int> f;
for (int v : adj[u]) {
f.push_back(v);
pq.erase({adj[v].size(), v});
adj[v].erase(u);
pq.emplace(adj[v].size(), v);
}
int m = f.size();
assert(m <= k);
fill(dp, dp + (1 << m), 0);
for (int i = 0; i < m; i++)
for (int j = 0; j < m; j++)
if (adj[f[i]].count(f[j]) || j == i)
con[i] |= 1 << j;
dp[0] = 1;
for (int i = 0; i < m; i++) {
for (int j = 1 << i; j < 2 << i; j++)
dp[j] = dp[j ^ 1 << i] & ((con[i] & j) == j);
}
for (int j = 0; j < 1 << m; j++) if (dp[j])
res = max(res, 1 + __builtin_popcount(j));
}
cout << res << '\n';
}
