// Slower C++ solution:
#include <iostream>

#include <iomanip>

#include <cstdio>

#include <string>

#include <cstring>

#include <deque>

#include <list>

#include <queue>

#include <stack>

#include <vector>

#include <utility>

#include <algorithm>

#include <map>

#include <set>

#include <complex>

#include <cmath>

#include <limits>

#include <cfloat>

#include <climits>

#include <ctime>

#include <cassert>

#include <numeric>

#include <functional>

using namespace std;



#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)

#define repq(i,a,n) for(int (i)=(a); (i)<=(n); (i)++)

#define repr(i,a,n) for(int (i)=(a); (i)>=(n); (i)--)

#define int long long int



template<typename T> void chmax(T &a, T b) {a = max(a, b);}

template<typename T> void chmin(T &a, T b) {a = min(a, b);}

template<typename T> void chadd(T &a, T b) {a = a + b;}



typedef pair<int, int> pii;

typedef long long ll;



int dx[] = {0, 0, 1, -1};

int dy[] = {1, -1, 0, 0};

constexpr ll INF = 1001001001001001LL;

constexpr ll MOD = 1000000007LL;



int N, M, K;

const int EXPN = 1 << 16;

int d[20], v[110][110];

bool dp[EXPN-1][30];

int dark[110];

int to[EXPN-1][110];

int dist[EXPN-1];

bool visited[EXPN-1];



signed main() {

    memset(dp, false, sizeof(dp));

    memset(dark, -1, sizeof(dark));

    memset(visited, false, sizeof(visited));

    cin >> N >> M >> K;

    rep(i,0,M) {

        cin >> d[i];

        d[i]--;

        // i ???????????????????????????????????? (????????´?????????????????????????????????)

        dark[ d[i] ] = i;

    }

    rep(i,0,N) rep(j,0,K) {

        cin >> v[i][j];

        v[i][j]--;

        // ???????????????????????°??????????????\??????

        if(dark[ v[i][j] ] == -1) v[i][j] = -1;

        else v[i][j] = dark[ v[i][j] ];

    }



    rep(j,0,K) {

        rep(bit,0,1<<M) {

            int nbit = 0;

            rep(i,0,M) {

                if(bit >> i & 1) {

                    if(v[d[i]][j] < 0) continue;

                    int val = 1 << v[d[i]][j];

                    nbit |= val;

                }

            }

            to[bit][j] = nbit;

        }

    }

    

    rep(i,0,1<<M) dist[i] = INF;

    dist[(1<<M)-1] = 0;

    queue<int> q;

    q.push((1<<M)-1);

    while(!q.empty()) {

        int t = q.front(); q.pop();

        rep(i,0,K) {

            int nx = to[t][i];

            if(dist[nx] > dist[t] + 1) {

                dist[nx] = dist[t] + 1;

                q.push(nx);

            }

        }

    }

    cout << dist[0] << endl;

    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.02298501576074x):
// #define _GLIBCXX_DEBUG // for STL debug (optional)

#include <iostream>

#include <iomanip>

#include <cstdio>

#include <string>

#include <cstring>

#include <deque>

#include <list>

#include <queue>

#include <stack>

#include <vector>

#include <utility>

#include <algorithm>

#include <map>

#include <set>

#include <complex>

#include <cmath>

#include <limits>

#include <cfloat>

#include <climits>

#include <ctime>

#include <cassert>

#include <numeric>

#include <fstream>

#include <functional>

#include <bitset>

using namespace std;

using ll = long long int;

using int64 = long long int;

 

template<typename T> void chmax(T &a, T b) {a = max(a, b);}

template<typename T> void chmin(T &a, T b) {a = min(a, b);}

template<typename T> void chadd(T &a, T b) {a = a + b;}

 

int dx[] = {0, 0, 1, -1};

int dy[] = {1, -1, 0, 0};

const int INF = 1LL << 29;

const ll LONGINF = 1LL << 60;

const ll MOD = 1000000007LL;

 

int main() {

    int N, M, K; cin >> N >> M >> K;

    vector<int> D(M);

    for(int i=0; i<M; i++) cin >> D[i], D[i]--;



    vector<int> id(N, -1);

    for(int i=0; i<M; i++) id[ D[i] ] = i;

    

    vector< vector<int> > to(N, vector<int>(K));

    for(int i=0; i<N; i++) {

        for(int j=0; j<K; j++) {

            cin >> to[i][j]; to[i][j]--;

        }

    }



    vector<int> dp(1<<M, INF);

    dp[(1<<M)-1] = 0;

    queue< pair<int, int> > que;

    que.emplace((1<<M)-1, 0);



    while(que.size()) {

        int bit, cost; tie(bit, cost) = que.front(); que.pop();

        if(dp[bit] < cost) continue;

        for(int i=0; i<K; i++) {

            int nbit = 0;

            for(int x=0; x<M; x++) {

                if(!(bit >> x & 1)) continue;

                int p = to[ D[x] ][i];

                if(id[p] >= 0) nbit |= (1 << id[p]);

            }

            if(dp[nbit] > dp[bit] + 1) {

                dp[nbit] = dp[bit] + 1;

                que.emplace(nbit, dp[nbit]);

            }

        }

    }

    printf("%d\n", dp[0]);

    return 0;

}