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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define st first
#define nd second

void solve() {
    int k, n; cin >> k >> n;
    vector<vector<int>> requirements(k+1);
    vector<vector<int>> attending(k+1);
    attending[1].resize(n+1);
    requirements[1].resize(n+1);
    for (int i = 2; i <= k; i++) {
        int m; cin >> m;
        requirements[i].resize(m+1);
        attending[i].resize(m+1);
        for (int j = 1; j <= m; j++) cin >> requirements[i][j];
    }
    int unassigned = 0;
    for (int i = k; i >= 1; i--) {
        for (int j = 1; j < attending[i].size(); j++) {
            if (attending[i][j] == 0) {
                if (unassigned > 0) unassigned--;
                attending[i][j]++;
            }
        }
        for (int j = 1; j < requirements[i].size(); j++) {
            if (requirements[i][j] == 0) unassigned += attending[i][j];
            else attending[i-1][requirements[i][j]] += attending[i][j];
        }
    }
    cout << unassigned << '\n';
}


int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
}