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#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
#include <queue>
#include <deque>
#include <tuple>
#include <bitset>

using namespace std;

#define pb push_back
#define mp make_pair
#define st first
#define nd second
#define x first
#define y second

typedef long long ll;
typedef pair<ll, ll> pii;
typedef pair<ll, ll> pll;
typedef vector<ll> vi;
typedef vector<ll> vll;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    
    ll k, n;
    cin >> k >> n;
    
    ll max_n = n;
    vector<vll> s(k-1);
    
    for(int i=0; i<k-1; i++){
        ll ni;
        cin >> ni;
        max_n = max(max_n, ni);
        s[i].resize(ni);
        for(int j=0; j<ni; j++){
            cin >> s[i][j];
        }
    }
    
    ll ans=n;
    ll cur=0;
    vll ansi(max_n, 0);
    vll prev(max_n, 0);

    for(int i=k-2; i>=0; i--){
        cur=0;
        for(int j=0; j<s[i].size(); j++){
            cur += max(1ll, ansi[j]);
            if(s[i][j]>0){
                prev[s[i][j]-1]+=max(1ll, ansi[j]);
            }
            ansi[j]=0;
        }
        ans = max(ans, cur);
        swap(ansi, prev);
    }

    cur=0;
    for(int j=0; j<n; j++){
        cur += max(1ll, ansi[j]);
    }
    ans = max(ans, cur);
    
    cout << ans << "\n";

    return 0;
}