#include <bits/stdc++.h>
using namespace std;
#ifdef MIKU
const string dbmc = "\033[1;38;2;57;197;187m", dbrs = "\033[0m";
#define debug(x...) cout << dbmc << "[" << #x << "]: ", dout(x)
void dout() { cout << dbrs << endl; }
template <typename T, typename ...U>
void dout(T t, U ...u) { cout << t << (sizeof...(u) ? ", " : ""); dout(u...); }
#else
#define debug(...) 39
#endif
#define int long long
#define fs first
#define sc second
#define mp make_pair
#define FOR(i, j, k) for (int i = j, Z = k; i < Z; i++)
typedef pair<int, int> pii;
const int MXN = 50005;
int n, k, ans = 1;
vector<int> edge[MXN];
int in[MXN];
bitset<MXN> ban;
set<pii> S;
unordered_set<int> EA;
bitset<1 << 10> dp;
int POPCNT(int I) {
return bitset<16>(I).count();
}
int calc(int id) {
debug(id);
ban[id] = true;
vector<int> v;
for (auto &i : edge[id]) {
if (ban[i]) continue;
S.erase(S.find(mp(in[i], i)));
S.insert(mp(--in[i], i));
v.push_back(i);
}
int n = v.size();
// for (auto &i : v) cout << i << ' ';
// cout << endl;
dp.reset();
dp[0] = true;
FOR(i, 0, n) {
int I = 0;
FOR(j, 0, i) if (EA.find(v[j] * MXN + v[i]) != EA.end()) I ^= (1 << j);
for (int j = I; true; j = ((j - 1) & I)) {
dp[j ^ (1 << i)] = dp[j];
if (j == 0) break;
}
}
int ans = 0;
FOR(I, 0, 1 << n) if (dp[I]) ans = max(ans, POPCNT(I));
return ans + 1;
}
void miku() {
int c, x;
cin >> n >> k;
FOR(i, 0, n) {
cin >> c;
while (c--) {
cin >> x;
edge[i].push_back(x);
EA.insert(i * MXN + x);
}
}
FOR(i, 0, n) S.insert(mp(in[i] = edge[i].size(), i));
FOR(i, 0, n) {
pii p = *S.begin();
S.erase(*S.begin());
ans = max(ans, calc(p.sc));
}
cout << ans << '\n';
}
int32_t main() {
cin.tie(0) -> sync_with_stdio(false);
cin.exceptions(cin.failbit);
miku();
return 0;
}
