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#include <bits/stdc++.h>
using namespace std;
#define fwd(i, a, n) for (int i = (a); i < (n); i++)
#define rep(i, n) fwd(i, 0, n)
#define all(X) X.begin(), X.end()
#define sz(X) int(size(X))
#define pb push_back
#define eb emplace_back
#define st first
#define nd second
using pii = pair<int, int>; using vi = vector<int>;
using ll = long long; using ld = long double;
#ifdef LOC
auto SS = signal(6, [](int) { *(int *)0 = 0; });
#define DTP(x, y) auto operator << (auto &o, auto a) -> decltype(y, o) { o << "("; x; return o << ")"; }
DTP(o << a.st << ", " << a.nd, a.nd);
DTP(for (auto i : a) o << i << ", ", all(a));
void dump(auto... x) { (( cerr << x << ", " ), ...) <<
'\n'; }
#define deb(x...) cerr << setw(4) << __LINE__ << ":[" #x "]: ", dump(x)
#else
#define deb(...) 0
#endif
 

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed << setprecision(10);
    int k, n; cin >> k >> n;
    vector<vi> prevMeeting(k);
    vector<vi> cnt(k);
    prevMeeting[0].resize(n, 0);
    cnt[0].resize(n, 0);
    fwd(i, 1, k){
        cin >> n;
        prevMeeting[i].resize(n);
        cnt[i].resize(n, 0);
        rep(j, n)cin>>prevMeeting[i][j];
    }
    deb(prevMeeting);
    deb(cnt);
    int res = 0;
    int current = 0;
    for(int i = k-1; i >= 0; i--){
        int finished = 0;
        rep(j, sz(prevMeeting[i])){
            if(cnt[i][j] == 0){
                cnt[i][j] = 1;
                current--;
                if(current < 0){
                    current = 0;
                    res++;
                }
            }
            if(prevMeeting[i][j]){
                deb(i, j, prevMeeting[i][j], cnt[i][j]);
                cnt[i-1][prevMeeting[i][j] - 1] += cnt[i][j];
            }else{
                finished += cnt[i][j];
            }
        }
        current += finished;
    }
    cout << res << "\n";
    return 0;
}