#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <cstring>
#include <queue>

using namespace std;

int N, M, K, C[2005], i, j;

vector<pair<int, int> > V[10005];

int D[2005];
int DIST[15][2005];

int solve(int ST, int DMIN[])
{
bool inQ[10005];

    queue<int> Q;
int i;
    for(i=1;i<=10005;++i)
        DMIN[i] = 0x3f3f3f3f, inQ[i] = false;

    Q.push(ST);
    DMIN[ST] = 0;
    inQ[ST] = true;

    while(!Q.empty())
    {
        int now = Q.front();
        inQ[now] = false;
        Q.pop();

        for(vector<pair<int, int> >::iterator it=V[now].begin();it!=V[now].end();++it)
            if(DMIN[now] + it->second < DMIN[it->first])
            {
                DMIN[it->first] = DMIN[now] + it->second;

                if(!inQ[it->first])
                {
                    Q.push(it->first);
                    inQ[it->first] = true;
                }

            }

    }

}

int main()
{

    freopen("ubuntzei.in", "r", stdin);
    freopen("ubuntzei.out", "w", stdout);

    cin>>N>>M;

    cin>>K;

    for(i=0;i<K;++i)
        cin>>C[i];

    for(i=1;i<=M;++i)
    {
        int A, B, z;
        scanf("%d %d %d", &A, &B, &z);
        V[A].push_back(make_pair(B, z));
        V[B].push_back(make_pair(A, z));
    }

    solve(1, D);

    if(K == 0)
        cout<<D[N]<<"\n";
    else
    {

        for(i=1;i<=K+1;++i)
            solve(C[i-1], DIST[i]);

/*
        for(i=1;i<=N;++i)
             cout<<(D[i] == 0x3f3f3f3f ? -1 : D[i])<<" ";
             cout<<"\n";
        for(i=1;i<=K;++i)
        {

            for(j=1;j<=N;++j)
                cout<<(DIST[i][j] == 0x3f3f3f3f ? -1 : DIST[i][j])<<" ";
            cout<<"\n";
        }
*/
        int rez = D[C[0]];

        for(i=1;i<K;++i)
            rez += DIST[C[i-1]-1][C[i]];

        rez += DIST[C[i-1]-1][N];

        while(next_permutation(C, C + K))
        {
            int rez_tmp = D[C[0]];

            for(i=1;i<K;++i)
                rez_tmp += DIST[C[i-1]-1][C[i]];

            rez_tmp += DIST[C[i-1]-1][N];

            if(rez_tmp < rez)
                rez = rez_tmp;

        }

        cout<<rez<<"\n";
    }
    return 0;
}