#include <cstdio>
#include <vector>
#include <set>

#define NMax 2001
#define Inf 1<<30

using namespace std;

long n, m, k, x, y, z, now, nr, minNr;
long a[21], b[21], cost[21][NMax];
vector<pair<long, long> > edge[NMax];
bool viz[21];


void computeMinimalRoadFrom ( long ind, long now ) {
    set<pair<long, long> > q;

    for ( long i = 1; i <= n; i++ )
        cost[ind][i] = Inf;

    q.insert ( make_pair ( 0, now ) );
    cost[ind][now] = 0;
    while ( !q.empty ( ) ) {
        now = q.begin ( )->second;
        q.erase ( q.begin ( ) );

        for ( long i = 0; i < edge[now].size ( ); i++ )
            if ( cost[ind][now] + edge[now][i].second < cost[ind][edge[now][i].first] )
                cost[ind][edge[now][i].first] = cost[ind][now] + edge[now][i].second,
                q.insert ( make_pair ( cost[ind][edge[now][i].first], edge[now][i].first ) );
    }
}

void bkt ( );

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

    scanf ( "%ld %ld %ld", &n, &m, &k );
    for ( long i = 1; i <= k; i++ )
        scanf ( "%ld", &a[i] );

    for ( long i = 1; i <= m; i++ )
        scanf ( "%ld %ld %ld", &x, &y, &z ),
        edge[x].push_back ( make_pair ( y, z ) ),
        edge[y].push_back ( make_pair ( x, z ) );


    a[0] = 1;
    a[k + 1] = n;
    for ( long i = 0; i <= k + 1; i++ )
        computeMinimalRoadFrom ( i, a[i] );

    minNr = Inf;
    bkt ( );

    printf ( "%ld\n", minNr );

    return 0;
}


void bkt ( ) {
    long kt = 1;
    while ( 0 < kt ) {
        if ( kt > k ) {
            long nr = 0;
            b[kt] = k + 1;
            for ( long i = 0; i <= k; i++ )
                nr += cost[b[i]][a[b[i + 1]]];

            if ( nr < minNr )
                minNr = nr;
            kt--;
        }

        viz[++b[kt]] = 0;
        while ( viz[b[kt]] == 1 && kt <= k )
            b[kt]++;

        if ( b[kt] > k )
            kt--;
        else
            viz[b[kt]] = 1,
            b[++kt] = 0;
    }
}