#include <fstream>
#include <vector>
#include <queue>
#define inf 2e9
using namespace std;
ifstream cin("ubuntzei.in");
ofstream cout("ubuntzei.out");
int n,m,k,x,y,c,d[20],dist[20][2001],dp[(1<<18)+1][20];
vector<pair<int,int>>v[2001];
bool viz[2001];
struct cmp{
    bool operator()(const pair<int,int>& a,const pair<int,int>& b){
        return a.second>b.second;
    }
};
priority_queue<pair<int,int>,vector<pair<int,int>>,cmp>q;
void dijkstra(int k){
    for(int i=1;i<=n;i++){
        dist[k][i]=inf;
        viz[i]=0;
    }
    q.push({d[k],0});
    dist[k][d[k]]=0;
    while(!q.empty()){
        int nod=q.top().first;
        q.pop();
        if(viz[nod])
            continue;
        viz[nod]=1;
        for(auto i:v[nod])
            if(!viz[i.first]&&dist[k][i.first]>dist[k][nod]+i.second){
                dist[k][i.first]=dist[k][nod]+i.second;
                q.push({i.first,dist[k][i.first]});
            }
    }
}
signed main()
{
    cin>>n>>m>>k;
    for(int i=1;i<=k;i++)
        cin>>d[i];
    for(int i=1;i<=m;i++){
        cin>>x>>y>>c;
        v[x].push_back({y,c});
        v[y].push_back({x,c});
    }
    d[0]=1,d[k+1]=n;
    for(int i=0;i<=k+1;i++)
        dijkstra(i);
    for(int i=0;i<(1<<(k+2));i++)
        for(int j=0;j<=k+1;j++)
            dp[i][j]=inf;
    dp[1][0]=0;
    for(int i=1;i<(1<<(k+2));i++){
        for(int j=0;j<=k+1;j++){
            if((i>>j)&1){
                for(int ii=0;ii<=k+1;ii++)
                    if(ii!=j&&((i>>ii)&1)){
                        dp[i][j]=min(dp[i][j],dp[i-(1<<j)][ii]+dist[ii][d[j]]);
                    }
            }
        }
    }
    cout<<dp[(1<<(k+2))-1][k+1];
    return 0;
}