#include<cstdio>
#include<algorithm>
#include<queue>
#include<vector>
using namespace std;

const int KMAX = 18;
const int NMAX = 2005;
const int INF = 1000000005;

int N, M, K;
vector< pair<int, int> > Graf[NMAX];
int vf[KMAX];
int dist[NMAX];
int lng[KMAX][KMAX];
int d[KMAX][(1<<KMAX)];

void citi()
{
	scanf("%d%d", &N, &M);
	scanf("%d", &K);
	for(int i = 1 ; i <= K ; i++)
		scanf("%d", &vf[i]);
	
	sort(vf + 1, vf + K + 1);
	if(vf[K] != N)	vf[++K] = N;
	if(vf[1] != 1)	vf[++K] = 1;
	sort(vf + 1, vf + K + 1);
	
	for(int i = 1 ; i <= M ; i++)
	{
		int x, y, c;
		scanf("%d%d%d", &x, &y, &c);
		Graf[x].push_back( make_pair(y, c) );
		Graf[y].push_back( make_pair(x, c) );
	}
}

void bellmanford(int pct)
{
	fill(dist + 1, dist + N + 1, INF);
	dist[vf[pct]] = 0;
	queue<int> Q;
	Q.push(vf[pct]);
	while(!Q.empty())
	{
		int x = Q.front();
		Q.pop();
		for(vector< pair<int, int> > :: iterator it = Graf[x].begin() ; it != Graf[x].end() ; it++)
			if(dist[it->first] > dist[x] + it->second)
			{
				dist[it->first] = dist[x] + it->second;
				Q.push(it->first);
			}
	}
	for(int i = 1; i <= K ; i++)
		lng[pct][i] = dist[vf[i]];
}

void dinamic()
{
	for(int i = 1 ; i <= K ; i++)
		for(int j = 0; j <= (1<<K) - 1 ; j++)
			d[i][j] = INF;
	d[1][1] = 0;
	
	for(int j = 0; j <= (1<<K) - 1 ; j++)
		for(int i = 1 ; i <= K ; i++)
			for(int l = 1 ; l <= K ; l++)
				if(l != i && j&(1<<(l-1)))
					d[i][j] = min(d[i][j], d[l][j - (1<<(i-1))] + lng[l][i]);
}

int main()
{
	freopen("ubuntzei.in", "r", stdin);
	freopen("ubuntzei.out", "w", stdout);
	citi();
	for(int i = 1 ; i <= K ; i++)
		bellmanford(i);
	dinamic();
	printf("%d\n", d[K][(1<<K) - 1]);
	return 0;
}