#include <bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <unordered_set>
using namespace std;
using namespace __gnu_pbds;
template<typename T>
using indexed_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
// const ll M = 998244353;
const ll M = 1e9 + 7;
#define all(v) (v).begin(), (v).end()
#define ff first
#define ss second
const ll INFL = 1e18;
const int INF = 1e9;
const int maxN = 50000;
bool dp[maxN][1<<10];
unordered_set<int> adj[maxN];
void solve() {
int n, k;
cin >> n >> k;
for (int i=0; i<n; i++) {
int d;
cin >> d;
for (int j=0; j<d; j++) {
int x;
cin >> x;
adj[i].insert(x);
}
}
vector<int> ord(n);
iota(all(ord), 0);
sort(all(ord), [](int l, int r) {
return adj[l].size() < adj[r].size();
});
int ans = 1;
for (auto i : ord) {
vector<int> cur;
for (auto v: adj[i]) cur.push_back(v);
dp[i][0] = true;
for (int msk=1; msk<1<<cur.size(); msk++) {
int p = __lg(msk);
bool ok = dp[i][msk^(1<<p)];
for (int j=0; j<p; j++) {
if (!(msk&(1<<j))) continue;
ok &= adj[cur[j]].count(cur[p]);
}
dp[i][msk] = ok;
if (ok) {
ans = max(ans, __builtin_popcount(msk)+1);
}
}
for (auto v: cur) adj[v].erase(i);
}
cout << ans << '\n';
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(NULL);
// cout << setprecision(12);
int tc = 1;
// cin >> tc;
while (tc--) solve();
}
