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#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <set>

using namespace std;


#define DEBUG false
#define log if (DEBUG) cerr
typedef long long ll;
typedef unsigned long long ull;

const ll MAX_TOTAL_LENGTH = 66000000;


static int numberOfTypes, adultLength;
static vector<vector<int>> replications;
static vector<int> adultSequence;
static vector<int> T;


static void readData()
{
    cin >> numberOfTypes >> adultLength;
    replications.resize(numberOfTypes + 1);
    for (int i = 1; i <= numberOfTypes; i++)
    {
        int repLength;
        cin >> repLength;
        replications[i].resize(repLength);
        for (auto& rep : replications[i])
        {
            cin >> rep;
        }
    }

    adultSequence.resize(adultLength);
    for (auto& adult : adultSequence)
    {
        cin >> adult;
    }
}

// https://en.wikibooks.org/wiki/Algorithm_Implementation/String_searching/Knuth-Morris-Pratt_pattern_matcher#C.2B.2B
static void computeT(const vector<int>& pattern, vector<int>& T)
{
    T.resize(pattern.size() + 1, -1);

    for(size_t i = 1; i <= pattern.size(); i++)
    {
        int pos = T[i - 1];
        while(pos != -1 && pattern[pos] != pattern[i - 1])
        {
            pos = T[pos];
        }
        T[i] = pos + 1;
    }
}

static bool KMP(const vector<int>& cells, const vector<int>& pattern, const vector<int>& T)
{
    size_t sp = 0;
    int kp = 0;
    while(sp < cells.size())
    {
        while(kp != -1 && (kp == pattern.size() || pattern[kp] != cells[sp]))
        {
            kp = T[kp];
        }
        kp++;
        sp++;
        if (kp == pattern.size())
        {
            return true;
        }
    }
    return false;
}

static ll computeNextLength(const vector<int>& cells)
{
    ll length = 0;

    for (auto cell : cells)
    {
        length += replications[cell].size();
    }

    return length;
}

static void solve()
{
    vector<int> cells[2];
    int src, dest;
    int age;
    int result;

    src = 0; dest = 1;
    cells[src].push_back(1);
    age = 2;
    computeT(adultSequence, T);

    while (true)
    {
        ll nextLength = computeNextLength(cells[src]);
        if (cells[src].size() + nextLength > MAX_TOTAL_LENGTH)
        {
            result = -1;
            break;
        }
        cells[dest].resize(nextLength);
        size_t j = 0;
        for (size_t i = 0; i < cells[src].size(); i++)
        {
            const vector<int>& replication = replications[cells[src][i]];
            for (int rep : replications[cells[src][i]])
            {
                cells[dest][j++] = rep;
            }
        }

        if (KMP(cells[dest], adultSequence, T))
        {
            result = age;
            break;
        }

        src = 1 - src;
        dest = 1 - dest;
        age ++;
    }

    cout << result;
}

static int findMinRep()
{
    size_t mini = 1001;

    for (size_t i = 1; i < replications.size(); i++)
    {
        mini = min(mini, replications[i].size());
    }

    return mini;
}

static void logCouple(const pair<vector<int>, vector<int>>& couple)
{
    if (DEBUG)
    {
        log << "[";
        for (auto a : couple.first) log << a << ",";
        log << "] -> ";
        for (auto a : couple.second) log << a;
        log << endl;
    }
}

static void logVector(const vector<int>& vec)
{
    if (DEBUG)
    {
        for (auto a : vec) log << a << ",";
        log << endl;
    }
}

static void solveShort()
{
    map<vector<int>, vector<int>> doubles;
    for (int i = 1; i <= numberOfTypes; i++)
    {
        vector<int> key = { i };
        doubles[key] = replications[i];
        for (int j = 1; j <= numberOfTypes; j++)
        {
            vector<int> key = { i, j };
            doubles[key] = replications[i];
            doubles[key].insert(doubles[key].end(), replications[j].begin(), replications[j].end());
        }
    }

    if (DEBUG)
    {
        log << "Doubles:" << endl;
        for (auto& couple : doubles)
        {
            logCouple(couple);
        }
    }

    set<vector<int>> visited;
    set<vector<int>> toVisit;
    vector<int> one = { 1 };

    toVisit.insert(adultSequence);
    visited.insert(adultSequence);
    int age = 2;
    int result = -1;

    while (!toVisit.empty())
    {
        set<vector<int>> newToVisit;
        for (const vector<int>& seq : toVisit)
        {
            vector<int> t;
            computeT(seq, t);
            logVector(seq);
            for (auto& couple : doubles)
            {
                if (KMP(couple.second, seq, t))
                {
                    log << "found: ";
                    logCouple(couple);
                    if (couple.first == one)
                    {
                        result = age;
                        goto end;
                    }
                    if (visited.find(couple.first) == visited.end())
                    {
                        visited.insert(couple.first);
                        newToVisit.insert(couple.first);
                    }
                }
            }
        }

        toVisit = newToVisit;
        age ++;
    }

end:
    cout << result;
}

int main()
{
    readData();
    if (adultLength == 1 && adultSequence[0] == 1)
    {
        cout << 1;
    }
    else
    {
        if (findMinRep() * 2 >= adultLength)
        {
            log << "short" << endl;
            solveShort();
        }
        else
        {
            log << "full" << endl;
            solve();
        }
    }
    return 0;
}