#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <bitset>
#include <cstring>
#define NMAX 2005
#define MMAX 10005
#define KMAX 18
#define inf 0x3f3f3f3f
using namespace std;

ifstream fin ("ubuntzei.in");
ofstream fout ("ubuntzei.out");

int n, m, k, u[KMAX], dist[KMAX][KMAX], d[NMAX], dp[1 << KMAX][KMAX];
vector <pair <int, int> > muchii[NMAX];
struct Drum {
	int nod, dist;
	Drum (int x, int y) {
		nod = x;
		dist = y;
	}
	bool operator<(const Drum& altu) const {
		return dist > altu.dist;
	}
};

void dijkstra (int node) {
	priority_queue <Drum> pq;
	memset(d, inf, sizeof(d));
	d[node] = 0;
	pq.push(Drum(node,0));
	while (pq.size()) {
		int cost = pq.top().dist;
		int nod = pq.top().nod;
		pq.pop();
		if (cost > d[nod]) {
			continue;
		}
		for (int i = 0; i < muchii[nod].size(); ++i) {
			if (d[muchii[nod][i].first] > cost + muchii[nod][i].second) {
				d[muchii[nod][i].first] = cost + muchii[nod][i].second;
				pq.push(Drum(muchii[nod][i].first,d[muchii[nod][i].first]));
			}
		}
	}
}

int main () 
{
	fin >> n >> m >> k;
	u[0] = 1;
	for (int i = 1; i <= k; ++i) {
		fin >> u[i];
	}
	u[++k] = n;
	++k;
	for (int i = 1; i <= m; ++i) {
		int x, y, z;
		fin >> x >> y >> z;
		muchii[x].push_back(make_pair(y,z));
		muchii[y].push_back(make_pair(x,z));
	}
	for (int i = 0; i < k; ++i) {
		dijkstra(u[i]);
		for (int j = 0; j < k; ++j) {
			dist[i][j] = d[u[j]];
		}
		dist[i][i] = 0;
	}
	memset(dp, inf, sizeof(dp));
	dp[1][0] = 0;
	int maxConf = (1 << k);
	for (int conf = 1; conf < maxConf; ++conf) {
		for (int i = 0; i < k; ++i) {
			if (conf & (1 << i)) {
				for (int j = 0; j < k; ++j) {
					if (conf & (1 << j)) {
						dp[conf][i] = min(dp[conf][i], dp[conf ^ (1 << i)][j] + dist[j][i]);
					}
				}
			}
		}
	}
	fout << dp[maxConf - 1][k - 1] << '\n';
	
	fin.close();
	fout.close();
	return 0;
}