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#include <bits/stdc++.h>
using namespace std;

const int MAXK = 500005;

vector<int> d[MAXK], cnt[MAXK];

int pool = 0;
int res = 0;

int main() {
	int k, n1;
	scanf("%d%d", &k, &n1);
	for (int i=0; i<n1; i++) {
		d[0].push_back(-1);
		cnt[0].push_back(0);
	}
	
	for (int i=1; i<k; i++) {
		int n, p;
		scanf("%d", &n);
		for (int j=0; j<n; j++) {
			scanf("%d", &p);
			d[i].push_back(p-1);
			cnt[i].push_back(0);
		}
	}
	
	for (int i=k-1; i>=0; i--) {
		for (int j=0; j<(int)d[i].size(); j++) {
			if (cnt[i][j] == 0) {
				if (pool == 0) {
					pool++;
					res++;
				}
				
				pool--;
				cnt[i][j]++;
			}
		}
		
		for (int j=0; j<(int)d[i].size(); j++) {
			if (d[i][j] == -1) {
				pool += cnt[i][j];
			}
			else {
				cnt[i-1][d[i][j]] += cnt[i][j];
			}
		}
	}
	
	printf("%d\n", res);
	
	return 0;
}