// 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;

    priority_queue< int, vector<int>, greater<int> > q;

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

    while(!q.empty()) {

        int t = q.top(); 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: 3.0167779474819656x):
// テ・ツ淞コテヲツ慊ャテ」ツδ?」ツδウテ」ツδ療」ツδャテ」ツδシテ」ツδ?



#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;

int dp[1<<16], to[1<<16][110];

int v[110][110];

int d[20], dark[110];



signed main() {

    cin >> N >> M >> K;

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

    rep(i,0,M) {

        cin >> d[i]; d[i]--;

        dark[ d[i] ] = i;

    }

    rep(i,0,N) rep(j,0,K) cin >> v[i][j], v[i][j]--;



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

        int nbit = 0;

        rep(k,0,M) {

            if(bit >> k & 1) {

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

                nbit |= (1 << dark[ v[d[k]][i] ]);

            }

        }

        to[bit][i] = nbit;

    }



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

    queue<int> q; q.push((1<<M)-1);

    while(!q.empty()) {

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

        rep(i,0,K) {

            int nbit = to[bit][i];

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

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

                q.push(nbit);

            }

        }

    }

    cout << dp[0] << endl;

    return 0;

}