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#include <cstdio>

// starting from day 1
int first_index_per_day[500000];
int last_index_per_day[500000];

struct Spotkanie
{
  Spotkanie* parent;
  int people;
  
  Spotkanie() : parent(nullptr), people(0) { }
};

Spotkanie spotkania[1000000];

int main()
{
  int k, n;
  scanf("%d%d", &k, &n);
  
  first_index_per_day[0] = 0;
  last_index_per_day[0] = n - 1;

  int next_index = n;
  for (int t=2; t<=k; ++t) {
    first_index_per_day[t-1] = next_index;
    scanf("%d", &n);
    for (int j=0; j<n; ++j) {
      int a; scanf("%d", &a);
      if (a > 0) {
        int parent_index = first_index_per_day[t-2] + a - 1;
        spotkania[next_index].parent = &spotkania[parent_index];
      }
      next_index++;
    }
    last_index_per_day[t-1] = next_index - 1;
  }
  int last_index = next_index - 1;

  for (int i=last_index; i>=0; --i) {
    if (!spotkania[i].people) {
      spotkania[i].people = 1;
    }
    if (spotkania[i].parent) {
      spotkania[i].parent->people += spotkania[i].people;
    }
  }

/*
  // kontrolne wypisywanie
  for (int t=0; t<k; ++t) {
    printf("DAY %d:\n", t+1);
    for (int i=first_index_per_day[t]; i<=last_index_per_day[t]; ++i) {
      if (spotkania[i].parent) {
        printf("spotkanie #%d jest kontynuacją #%ld: %d\n", i, spotkania[i].parent - spotkania, spotkania[i].people);
      } else {
        printf("spotkanie #%d nie jest kontynuacją: %d\n", i, spotkania[i].people);
      }
    }
  }
*/

  int max_total_people = 0;
  for (int t=0; t<k; ++t) {
    int total_people = 0;
    for (int i=first_index_per_day[t]; i<=last_index_per_day[t]; ++i) {
      total_people += spotkania[i].people;
    }
    if (total_people > max_total_people) {
      max_total_people = total_people;
    }
  }
  printf("%d\n", max_total_people);
}