#include <cstdio>
#include <vector>
#include <set>
#define minim(a, b) ((a < b) ? a : b)
#define INF 999999999
#define KMAX 15
#define NMAX 2005
#define pii pair<int, int>
#define f first
#define s second
#define mp make_pair
#define pb push_back


using namespace std ;

int N , M , K , C[KMAX] ;
int source[NMAX] , path[KMAX][NMAX] ;
vector < pii > G[NMAX] ;
int pd[ 1 << KMAX ][KMAX] ;
set < pii > q ;

inline int bit( int x , int nr )
{
    return ( x & ( 1 << nr ) ) != 0 ;
}
void dijkstra( int sursa , int *sol )
{
    int i , vec ;
    for ( i = 1 ; i <= N ; ++i )
        sol[i] = INF ;
    sol[sursa] = 0 ;
    q.clear() ;
    for ( i = 1 ; i <= N ; ++i )
        q.insert( mp ( sol[i] , i ) ) ;
    for ( i = 1 ; i < N ; ++i )
    {
        pii top = *q.begin() ;
        q.erase(q.begin()) ;
        int nod = top.s ;
        for ( size_t j = 0 ; j < G[nod].size() ; ++j )
            if ( sol[vec = G[nod][j].f] > sol[nod] + G[nod][j].s )
            {
                q.erase( mp ( sol[vec], vec ) ) ;
                sol[vec] = sol[nod] + G[nod][j].s ;
                q.insert( mp ( sol[vec], vec ) ) ;
            }
    }
}

int main()
{
    int i , j , k , newCost ;
    freopen( "ubuntzei.in" , "r" , stdin ) ;
    freopen( "ubuntzei.out" , "w" , stdout ) ;
    scanf( "%d %d %d" , &N , &M , &K ) ;
    for ( i = 0 ; i < K ; ++i )
        scanf( "%d" , &C[i] ) ;
    for ( ; M ; --M )
    {
        scanf( "%d %d %d" , &i , &j , &k ) ;
        G[i].pb( mp ( j , k ) ) ;
        G[j].pb( mp ( i , k ) ) ;
    }
    dijkstra( 1, source ) ;
    if ( K == 0 )
    {
        printf( "%d\n" , source[N] ) ;
        return 0 ;
    }
    for ( i = 0 ; i < K ; ++i )
        dijkstra( C[i] , path[i] ) ;
    for ( i = 1 ; i < ( 1 << K ) ; ++i )
    {
        for ( j = 0 ; j < K ; ++j )
            if ( i == ( 1 << j ) )
                break ;
        if ( j < K && i == ( 1 << j ) )
        {
            pd[i][j] = source[C[j]] ;
            continue ;
        }
        for ( j = 0 ; j < K ; ++j )
        {
            pd[i][j] = INF ;
            if ( bit( i , j ) )
                for ( k = 0 ; k < K ; ++k )
                    if (k != j && bit( i , k ) )
                    {
                        newCost = pd[ i - ( 1 << j ) ][k] + path[k][C[j]] ;
                        pd[i][j] = minim( pd[i][j] , newCost) ;
                    }
        }
    }
    int bst = INF ;
    for (i = 0 ; i < K ; ++i )
        bst = minim( bst , pd[( 1 << K ) - 1 ][i] + path[i][N]) ;
    printf( "%d\n" , bst ) ;
    return 0 ;
}