#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using arr = array<int, 2>;
constexpr int maxn = 5e4;
bool visited[maxn] = { 0 };
set<int> adj[maxn];
int k;
int output = 1;
void dfs(int pos)
{
// cout << pos << endl;
visited[pos] = true;
vector <bitset<10>> v(adj[pos].size());
int ii = 0; // Counts which place it is in the order of adj[pos]
int iii;
for (int i : adj[pos])
{
auto it = adj[pos].begin();
auto ft = adj[i].begin();
iii = 0;
v[ii][ii] = true;
while (it != adj[pos].end() && ft != adj[i].end())
{
if (*it < *ft)
{
it++;
iii++;
continue;
}
if (*ft < *it)
{
ft++;
continue;
}
v[ii][iii] = true;
it++, ft++;
iii++;
}
ii++;
}
bitset<10> all;
for (int i = 1; i < (1 << (adj[pos].size())); i++){
all.set();
for (size_t y = 0; y < adj[pos].size(); y++) {
if (i & (1 << y)) all &= v[y];
}
// cout << i << " " << all << "\n";
if (__builtin_popcount(i) == all.count()) output = max(output, __builtin_popcount(i) + 1);
}
for (int i : adj[pos]) adj[i].erase(pos);
for (int i : adj[pos]) if ((int)adj[i].size() <= k) dfs(i);
}
int main()
{
// ios_base::sync_with_stdio(false);
// cin.tie(NULL);
int n;
cin >> n >> k;
for (int i = 0; i < n; i++)
{
int a, b;
cin >> a;
for (int y = 0; y < a; y++)
{
cin >> b;
adj[i].insert(b);
}
}
// for (int i = 0; i < n; i++)
// {
// for (int y : adj[i]) cout << y << " ";
// cout << "\n";
// }
for (int i = 0; i < n; i++) if (!visited[i] && (int)adj[i].size() <= k) dfs(i);
cout << output << "\n";
cerr << clock() / static_cast<double>(CLOCKS_PER_SEC) << "\n";
}
