#include <bits/stdc++.h>
using namespace std;
#define ios ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin() + 1, (x).rend()
#define fi first
#define se second
#define yes cout << "YES" << '\n'
#define no cout << "NO" << '\n'
#define int long long
#define veci vector<int>
#define skip continue
#define sz size()
#define pii pair<int,int>
const int mod = 1e9 + 7;
const int N = 52;
const int inf = 1e18;
void zertinii() {
int n, m;
cin >> n >> m;
bool ok = false;
veci a(n + 1);
int c[n][n];
for(int i = 1;i <= n;i++) {
cin >> a[i];
veci b(a[i] + 1);
if(a[i] > 0) {
ok = true;
}
for(int j = 1;j <= a[i];j++) {
cin >> b[j];
c[i][b[j]] = 1;
c[b[j]][i] = 1;
}
}
if(m == 1) {
cout << 1;
return;
}
else {
if(ok) {
cout << 2;
return;
}
else {
cout << 1;
return;
}
}
for(int i = 1;i <= n;i++) {
for(int j = i + 1;j <= n;j++) {
if(!c[i][j]) {
continue;
}
else {
break;
}
for(int k = j + 1;k <= n;k++) {
if(c[i][k] and c[j][k]) {
cout << 3;
return;
}
}
}
}
if(ok) {
cout << 2;
}
else {
cout << 1;
}
}
signed main() {
ios;
int t = 1;
//cin >> t;
while(t--) {
zertinii();
}
return 0;
}
