//Oh? You're Approaching Me?
#include <bits/stdc++.h>
using namespace std;
//#define int long long
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
// #pragma GCC optimize("O3,unroll-loops")
#define migmig ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define pb push_back
#define F first
#define S second
#define SZ(x) ll((x).size())
#define all(x) (x).begin(), (x).end()
#define cl clear
#define endl '\n'
#define deb(x) cerr << #x << " = " << x << '\n'
#define dokme(x) {cout << x << endl; return;}
#define wtf cout << "[ahaaaaaaaaaaaaaaaa]" << endl;
const int maxn = 2e5 + 21;
const int mod = 998244353;
//const int inf = 1e18;
const int LOG = 23;
const int sq = 300;
//g++ main.cpp -o main && main.exe
//#define lc (id * 2)
//#define rc (lc + 1)
//#define mid ((l + r) / 2)
bool dp[maxn][1<<10];
unordered_set<int> adj[maxn];
signed main() {
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 (int i : ord) {
vector<int> cur;
for (auto v : adj[i]) {
cur.pb(v);
}
dp[i][0] = true;
for (int mask = 1; mask < (1 << SZ(cur)); mask++) {
int p = __lg(mask);
bool ok = dp[i][mask ^ (1 << p)];
for (int j = 0; j < p; j++) {
if (!(mask & (1 << j)))
continue;
ok &= adj[cur[j]].count(cur[p]);
}
dp[i][mask] = ok;
if (ok) {
ans = max(ans, __builtin_popcount(mask) + 1);
}
}
for (auto v: cur) adj[v].erase(i);
}
cout << ans << '\n';
}
