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#include <bits/stdc++.h>

const int MAX_N = 6e5;
std::vector<int> list[MAX_N + 3];
int val[MAX_N + 3];
int day[MAX_N + 3];
bool visited[MAX_N + 3];
int day_sum[MAX_N + 3];

int k, n;

void input() {
  int n1, n2, prev;
  std::cin >> k >> n1;
  n = n1;

  for (int i = 1; i <= n1; i++)
    day[i] = 1;

  for (int j = 2; j <= k; j++) {
    std::cin >> n2;
    for (int i = n + 1; i <= n + n2; i++) {
      std::cin >> prev;
      day[i] = j;

      if (prev != 0) {
        list[n - n1 + prev].push_back(i);
      }
    }
    n1 = n2;
    n += n2;
  }

  for (int i = 1; i <= k; i++)
    day_sum[i] = 0;

  for (int i = 1; i <= n; i++) {
    val[i] = 0;
    visited[i] = false;
  }
}

void dfs(int v) {
  visited[v] = true;

  if (list[v].empty())
    val[v] = 1;
  else {
    for (auto u : list[v]) {
      dfs(u);
      val[v] += val[u];
    }
  }
}

int main() {
  std::ios_base::sync_with_stdio(0);
  std::cin.tie(NULL);

  input();

  for (int i = 1; i <= n; i++)
    if (!visited[i])
      dfs(i);

  for (int i = 1; i <= n; i++)
    day_sum[day[i]] += val[i];

  int result = 0;
  for (int i = 1; i <= k; i++)
    result = std::max(result, day_sum[i]);

  std::cout << result << "\n";
}