#include <bits/stdc++.h>
using namespace std;

const int INF = 1 << 26;
struct Edge {
	int u, v, c;
	bool operator<(const Edge& other) const {
		return c < other.c;
	}
};

int N, M, T, ts[50];
Edge E[777];
int dist[50][50];

int root[50];
inline int find(int x){
	if(x == root[x])return x;
	return root[x] = find(root[x]);
}
inline bool conn(int x, int y){
	x = find(x);
	y = find(y);
	if(x == y)return false;

	root[x] = y;
	return true;
}


int rest_v[50];
int use[50];
inline int min_spanning_tree(){
	for(int i=0;i<N;i++)root[i] = i;

	int res = 0;
	for(int i=0;i<M;i++){
		int u = E[i].u, v = E[i].v, c = E[i].c;
		if(!use[u] || !use[v])continue;
		if(conn(u, v)){
			res += c;
		}
	}

	for(int i=0;i<T;i++){
		if(find(ts[i]) != find(ts[0]))return INF;
	}

	return res;
}

int dp[1<<15][50];
int min_steiner_tree(){
  for(int i=0;i<N;i++)for(int j=0;j<N;j++)dist[i][j] = INF;
  for(int i=0;i<N;i++)dist[i][i] = 0;
  for(int i=0;i<M;i++){
  	int u = E[i].u, v = E[i].v, c = E[i].c;
  	dist[u][v] = c;
  	dist[v][u] = c;
  }

  for(int k=0;k<N;k++)for(int i=0;i<N;i++)for(int j=0;j<N;j++){
  	dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);
  }
  

  if(T < 2)return 0;
  for(int i=0;i<T;i++)for(int j=0;j<N;j++){
  	dp[1 << i][j] = dist[ts[i]][j];
  }

  for(int i=1;i<1<<T;i++)if(((i - 1) & i) != 0){
  	for(int j=0;j<N;j++){
  		dp[i][j] = INF;
  		for(int k=(i-1)&i; k > 0; k = (k - 1) & i){
  			dp[i][j] = min(dp[i][j], dp[k][j] + dp[i^k][j]);
  		}
  	}
  	for(int j=0;j<N;j++){
  		for(int k=0;k<N;k++){
  			dp[i][j] = min(dp[i][j], dp[i][k] + dist[k][j]);
  		}
  	}
  }

  return dp[(1 << T)-1][ts[0]];
}

int main(){
	cin >> N >> M >> T;
	for(int i=0;i<M;i++){
		int u, v, c;
		cin >> u >> v >> c;
		E[i] = Edge{u - 1, v - 1, c};
	}
	for(int i=0;i<T;i++)cin >> ts[i], ts[i]--;

	int res;
	if(T <= 14){
		res = min_steiner_tree();
	} else {
		for(int i=0;i<T;i++)use[ts[i]] = true;

		int rest = 0;
		for(int i=0;i<N;i++)if(!use[i]){
			rest_v[rest++] = i;
		}

		sort(E, E + M);
		res = INF;

		for(int mask=0;mask<1<<rest;mask++){
			for(int i=0;i<rest;i++){
				if((mask >> i) & 1){
					use[rest_v[i]] = true;
				}
			}

			res = min(res, min_spanning_tree());

			for(int i=0;i<rest;i++){
				if((mask >> i) & 1){
					use[rest_v[i]] = false;
				}
			}
		}
	}

	cout << res << endl;
	return 0;
}