#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int N, K;
cin >> N >> K;
vector<int> deg(N);
vector<vector<int>> adj(N);
for (int u = 0; u < N; u++) {
int sz;
cin >> sz;
while (sz--) {
int v;
cin >> v;
deg[u]++;
adj[u].emplace_back(v);
}
}
vector<int> done(N);
priority_queue<pair<int, int>> pq;
for (int u = 0; u < N; u++) {
sort(begin(adj[u]), end(adj[u]));
pq.emplace(-deg[u], u);
}
int ans = 0;
while (!pq.empty()) {
int mn = pq.top().second;
pq.pop();
if (done[mn]) {
continue;
}
done[mn] = 1;
static vector<int> ls; ls = {mn};
for (auto v : adj[mn]) if (!done[v]) {
ls.emplace_back(v);
deg[v]--;
pq.emplace(-deg[v], v);
}
int n = ls.size();
assert(n <= K);
static array<int, 10> arr;
for (int i = 0; i < n; i++) {
arr[i] = 1 << i;
}
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
int u = ls[i], v = ls[j];
if (binary_search(begin(adj[u]), end(adj[u]), v)) {
arr[i] |= 1 << j;
arr[j] |= 1 << i;
}
}
}
for (int mask = 1; mask < (1 << n); mask++) {
int valid = mask;
for (int i = 0; i < n; i++) if ((mask >> i) & 1) {
valid &= arr[i];
}
if (valid == mask) {
ans = max(ans, __builtin_popcount(mask));
}
}
}
cout << ans << '\n';
return 0;
}
