/*
ID: varunra2
LANG: C++
TASK: politicaldevelopment
*/
#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif
#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second
const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;
#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions
int n, k;
vector<SETI> adj;
VI deg;
vector<bool> use;
int mx = 0;
void init() {
adj.resize(n);
deg.assign(n, 0);
use.assign(n, false);
}
int main() {
// #ifndef ONLINE_JUDGE
// freopen("politicaldevelopment.in", "r", stdin);
// freopen("politicaldevelopment.out", "w", stdout);
// #endif
cin.sync_with_stdio(0);
cin.tie(0);
cin >> n >> k;
init();
for (int i = 0; i < n; i++) {
int d;
cin >> d;
for (int j = 0; j < d; j++) {
int u;
cin >> u;
adj[i].insert(u);
adj[u].insert(i);
}
}
rep(u, 0, n) trav(v, adj[u]) { deg[u]++; }
queue<int> q;
for (int i = 0; i < n; i++) {
if (deg[i] <= k) q.push(i);
}
// debug(deg);
// debug(q);
while (!q.empty()) {
// debug("debugging adj :imp:");
// trav(x, adj) debug(x);
int u = q.front();
q.pop();
VI cur;
trav(x, adj[u]) if (!use[x]) cur.PB(x);
for (int i = 0; i < (1 << sz(cur)); i++) {
int val = __builtin_popcount(i);
if (val < mx) continue;
VI now;
now.PB(u);
for (int j = 0; j < sz(cur); j++) {
if (i & (1 << j)) now.PB(cur[j]);
}
bool ok = true;
for (int j = 0; j < sz(now) and ok; j++) {
for (int kk = j + 1; kk < sz(now) and ok; kk++) {
if (adj[now[j]].find(now[kk]) == adj[now[j]].end()) ok = false;
}
}
// debug(cur)
if (ok) mx = max(mx, val + 1);
}
use[u] = true;
for (auto& x : cur) {
adj[x].erase(u), deg[x]--;
if (deg[x] <= k) q.push(x);
adj[u].erase(x);
}
}
cout << mx << '\n';
return 0;
}
