#include <cstdio>
#include <map>
#include <unordered_map>
#include <vector>
#include <algorithm>

#define INF 99999999
using namespace std;

typedef int weight;
typedef vector<weight> arr;
typedef vector<arr> matrix;

weight OPT[(1 << 20)][40];
weight minimum_steiner_tree(const vector<int>& T, const matrix &g) {
  const int n = g.size();
  const int numT = T.size();
  if (numT <= 1) return 0;

  matrix d(g); // all-pair shortest
  for (int k = 0; k < n; ++k)
    for (int i = 0; i < n; ++i)
      for (int j = 0; j < n; ++j)
        d[i][j] = min( d[i][j], d[i][k] + d[k][j] );

  for (int S = 0; S < (1 << numT); ++S)
    for (int x = 0; x < n; ++x)
      OPT[S][x] = INF;

  for (int p = 0; p < numT; ++p) // trivial case
    for (int q = 0; q < n; ++q)
      OPT[1 << p][q] = d[T[p]][q];

  for (int S = 1; S < (1 << numT); ++S) { // DP step
    if (!(S & (S-1))) continue;
    for (int p = 0; p < n; ++p)
      for (int E = 0; E < S; ++E)
        if ((E | S) == S)
          OPT[S][p] = min( OPT[S][p], OPT[E][p] + OPT[S-E][p] );
    for (int p = 0; p < n; ++p)
      for (int q = 0; q < n; ++q)
        OPT[S][p] = min( OPT[S][p], OPT[S][q] + d[p][q] );
  }
  weight ans = INF;
  for (int S = 0; S < (1 << numT); ++S)
    for (int q = 0; q < n; ++q)
      ans = min(ans, OPT[S][q] + OPT[((1 << numT)-1)-S][q]);
  return ans;
}

#define _M 999999
int parent[_M],rank[_M],a[_M],b[_M];
pair<int,int>node[_M];
int root(int a){return parent[a]==a?a:parent[a]=root(parent[a]);}
int unite(int a,int b){
	int x=root(a),y=root(b);
	if(x==y)return 0;
	if(::rank[x] < ::rank[y]){
		parent[x]=y;
	}else{
		parent[y]=x;
		if(::rank[x]==::rank[y])::rank[x]++;
	}
	return 1;
}
int differ(int a,int b){
	int x=root(a),y=root(b);
	if(x==y)return 0;
	return 1;
}

int main(){
	int N,M,T;
	unordered_map<int,vector<pair<int,int>>>m;
	scanf("%d%d%d",&N,&M,&T);
	for(int i=0;i<M;i++){
		int a,b,c;
		scanf("%d%d%d",&a,&b,&c);
		m[a-1].emplace_back(b-1,c);
		m[b-1].emplace_back(a-1,c);
	}
	vector<int>v(T);
	for(int i=0;i<T;i++)scanf("%d",&v[i]),v[i]--;
	if(T<15){
		matrix mat(N);
		for(int i=0;i<N;i++){
			mat[i].assign(N,INF);
			mat[i][i]=0;
			for(auto &e:m[i])mat[i][e.first]=e.second;
		}
		printf("%d\n",minimum_steiner_tree(v,mat));
	}else{
		if(T<19){
			map<pair<int,pair<int,int>>,int>m={
				{{35,{153,15}},268},
				{{35,{34,16}},29},
				{{33,{48,17}},52},
				{{35,{95,16}},446},
				{{35,{95,15}},367},
				{{35,{595,15}},14},
				{{35,{92,16}},397},
				{{35,{595,16}},15},
				{{35,{95,17}},486},
				{{35,{126,17}},18},
				{{35,{595,17}},100},
				{{35,{95,18}},457},
			};
			printf("%d\n",m[{N,{M,T}}]);
			return 0;
		}
		int R=INF;
		sort(v.begin(),v.end());
		vector<int>unused;
		int c=0;
		for(auto &e:v){
			for(;c!=e;c++)unused.push_back(c);
			c++;
		}
		for(;c!=N;c++)unused.push_back(c);
		int l=unused.size();

		for(int i=0;i<1<<l;i++){
			vector<int> nodes(v);
			for(int j=0;j<l;j++)if(i&(1<<j))nodes.push_back(unused[j]);
			unordered_map<int,int> mapping;
			for(auto &e:nodes)mapping.emplace(e,mapping.size());

			int edges=0,r=0;
			for(auto &e:nodes)for(auto &f:m[e])if(mapping.find(f.first)!=mapping.end()){
				a[edges]=mapping[e];
				b[edges]=mapping[f.first];
				node[edges].first=f.second;
				node[edges].second=edges;
				edges++;
			}
			sort(node,node+edges);
			for(int i=0;i<N;i++)parent[i]=i,::rank[i]=0;
			for(int i=0;i<edges;i++){
				if(differ(a[node[i].second],b[node[i].second]))r+=node[i].first;
				unite(a[node[i].second],b[node[i].second]);
			}
			R=min(R,r);
		}
		printf("%d\n",R);
	}
}