#include <bits/stdc++.h>
#include <iostream>
#include <vector>
#include <queue>
#include <string>
#include <cstring>
#include <sstream>
#include <set>
#include <map>
#include <algorithm>
#include <cstdio>
#include <cstdlib>

#define rep(i,n) for(int i=0;i<(int)(n);++i)
#define iter(a) __typeof(a.begin())
#define FOR(it,a) for(iter(a)it=a.begin();it!=a.end();++it)
#define F first
#define S second
#define SZ(a) (int)((a).size())
#define sz(a) SZ(a)
#define pb(a) push_back(a)
#define mp(a,b) make_pair(a,b)
#define ALL(a) (a).begin(),(a).end()
using namespace std;

typedef long long ll;
typedef pair<int,int> PI;
typedef unsigned long long ull;

#define PR(...) do{cerr << "line : " << __LINE__ << endl; pr(#__VA_ARGS__, __VA_ARGS__);}while(0);
template<class T>
void pr(const string& name, T t){
  cerr << name << ": " << t << endl;
}

template<typename T, typename ... Types>
void pr(const string& names, T t, Types ... rest) {
  auto comma_pos = names.find(',');
  cerr << names.substr(0, comma_pos) << ": " << t << ", ";
  
  auto next_name_pos = names.find_first_not_of(" \t\n", comma_pos + 1);
  pr(string(names, next_name_pos), rest ...);
}

template<class T,class U> ostream& operator<< (ostream& o, const pair<T,U>& v){return o << "(" << v.F << ", " << v.S << ")";}
template<class T> ostream& operator<< (ostream& o, const vector<T>& v){o << "{";rep(i,SZ(v)) o << (i?", ":"") << v[i];return o << "}";}

const int dx[] = {0,1,0,-1};
const int dy[] = {-1,0,1,0};
#define endl '\n'

const int MAX_N=40;
int cost[MAX_N][MAX_N];
const int THRESHOLD=15;

int dp[1<<THRESHOLD][MAX_N];
int un[MAX_N];
int find(int x){
  if(x == un[x]) return x;
  return un[x] = find(un[x]);
}

void unit(int a,int b){
  un[find(a)] = find(b);
}

bool db[100][100];

int main(int argc, char *argv[])
{
  int n,m,t;
  cin >> n >> m >> t;
  rep(i,n)rep(j,n) cost[i][j] = 1e9;
  vector<pair<int,PI > > ed;
  rep(i,m){
    int a,b,c;
    cin >> a >> b >> c;
    --a,--b;
    ed.pb(mp(c,mp(a,b)));
    cost[b][a] = cost[a][b] = min(cost[a][b],c);
  }
  rep(i,n) cost[i][i] = 0;
  rep(k,n)rep(i,n)rep(j,n){
    if(cost[i][j] >= cost[i][k] + cost[k][j] && i != k && k != j){
      db[i][j] = 1;
      db[j][i] = 1;
    }
    cost[i][j] = min(cost[i][j], cost[i][k]+cost[k][j]);
  }
  
  vector<int> terminal(t);
  rep(i, t){
    cin >> terminal[i];
    --terminal[i];
  }
  
  if(t>THRESHOLD){
    sort(ALL(ed));
    {
      vector<pair<int,PI> > ned;
      for(auto e : ed) if(!db[e.S.F][e.S.S]) ned.pb(e);
      ed = ned;
    }
    //PR(m,SZ(ed));
    
    vector<int> nont;
    sort(ALL(terminal));
    rep(i,n)
      if(!binary_search(ALL(terminal),i))
        nont.pb(i);
    //cout << nont << endl;
    int ans = 1e9;
    rep(i,1<<(n-t)){
      bool use[35] = {};
      int comp = t-1;
      rep(j,n-t) comp += use[nont[j]] = (i>>j)&1;
      rep(j,t) use[terminal[j]] = true;
      rep(j,n) un[j] = j;
      int cc = 0;
      
      for(const auto& e : ed){
        if(!use[e.S.F] || !use[e.S.S]) continue;
        int a = find(e.S.F);
        int b = find(e.S.S);
        if(a != b){
          un[a] = b;
          cc += e.F;
          --comp;
          if(cc >= ans || comp==0) break;
        }
      }
      if(cc >= ans || comp) continue;
      ans = cc;
    }
    
    cout << ans << endl;
  }else{
    rep(S,1<<t)rep(i,n) dp[S][i] = 1e9;
    rep(i,t)rep(j,n) dp[1<<i][j] = cost[terminal[i]][j];
    
    for(int S = 3; S < (1<<t); ++S){
      if(!(S & (S-1))) continue;
      int sub = (S-1) & S;
      do{
        rep(i,n) dp[S][i] = min(dp[S][i], dp[sub][i] + dp[sub^S][i]);
        sub = (sub-1) & S;
      }while(sub);
      rep(p,n)rep(q,n)
        dp[S][p] = min(dp[S][p], dp[S][q]+cost[q][p]);
    }
    
    cout << dp[(1<<t)-1][terminal[0]] << endl;
  }
  
  return 0;
}