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#include <iostream>
#include <vector>
using namespace std;
#include <stdio.h>

bool isTheSame(int n, vector<int> a, vector<int> b){
    for(int i = 0; i < n; i++)
        if(a[i] != b[i]) return false;
    return true;
}

int main(void){
    int n, k, tmp, packageLoc, oldLoc, cnt = 0;
    string s;
    cin >> n;
    vector<vector<int> > row(n);
    vector<int> pointer(n,0);
    vector<int> origPointer(n,0);
    for(int i = 0; i < n; i++){
        cin >> k;
        for(int j = 0; j < k; j++){
            cin >> tmp;
            row[i].push_back(tmp - 1);
        }
    }
    for(int i = 0; i < n; i++){
        if(row[i].size() == 0)
            pointer[i] = origPointer[i] = -1;
    }
    //printf("done\n");
    //for(int i = 0; i < n; i++){
    //    for(int j = 0; j < row[i].size(); j++)
    //        printf("%d ", row[i][j]);
    //    //printf("\n");
    //}
    //for(int i = 0; i < n; i++)
    //    printf("%d ", pointer[i]);

    //do a single flow
    packageLoc = 0;
    do{
        packageLoc = 0;
        while(pointer[packageLoc] != -1){
            oldLoc = packageLoc;
            packageLoc = row[packageLoc][pointer[packageLoc]];
            pointer[oldLoc] = (pointer[oldLoc] + 1) % row[oldLoc].size();
            //printf("Package moved from %d to %d\n", oldLoc+1, packageLoc+1);
        }
        //printf("Pointers: ");
        //for(int i = 0; i < n; i++)
        //    printf("%d ", pointer[i]);
        //printf("\n");
        cnt++;
    }while((!isTheSame(n, pointer, origPointer)));
    printf("%d", cnt);
    return 0;
}