#include <fstream>
#include <vector>
#include <set>
#define inf 0x7fffffff
using namespace std;
ifstream cin("ubuntzei.in");
ofstream cout("ubuntzei.out");
const int lim=2003;
int v[lim],c[17];
vector<pair<int,int> > vec[lim];
int dist[20][lim];
int n,m,k,x,y,z;
vector<int> prez;
int dp[20][32800];
void dijkstra(int ind)
{
    set<pair<int,int> > s;
    for(int i=1;i<=n;++i)
        dist[ind][i]=inf;
    dist[ind][c[ind]]=0;
    s.insert({0,c[ind]});
    while(!s.empty())
    {
        int x=(*(s.begin())).second;
        s.erase(s.begin());
        if(dist[ind][x]==inf) continue;
        for(auto t:vec[x])
        if(dist[ind][t.first]>dist[ind][x]+t.second)
        {
            if(dist[ind][t.first]!=inf)
                s.erase(s.find({dist[ind][t.first],t.first}));
            dist[ind][t.first]=dist[ind][x]+t.second;
            s.insert({dist[ind][t.first],t.first});
        }
    }
}
int main()
{
    cin>>n>>m>>k;
    c[0]=1;
    c[k+1]=n;
    for(int i=1;i<=k;++i)
        cin>>c[i];
    for(int i=1;i<=m;++i)
    {
        cin>>x>>y>>z;
        vec[x].push_back({y,z});
        vec[y].push_back({x,z});
    }
    for(int i=0;i<=k+1;++i)
        dijkstra(i);
    int poz=(1<<k)-1;
    for(int r=1;r<=poz;++r)
    {
        int mask=r;
        prez.clear();
        for(int i=1;i<=k;++i)
        {
            if(mask%2) prez.push_back(i);
            mask/=2;
        }
        if(prez.size()==1)
        {
            dp[prez[0]][r]=dist[0][c[prez[0]]];
            continue;
        }
        for(auto i:prez)
        {
            dp[i][r]=inf;
            for(auto j:prez) if(i!=j)
            dp[i][r]=min(dp[i][r],dp[j][r-(1<<(i-1))]+dist[j][c[i]]);
        }
    }
    int ans=inf;
    for(int i=1;i<=k;++i)
    if(dp[i][poz]!=inf)
        ans=min(ans,dp[i][poz]+dist[i][n]);
    cout<<ans;
    return 0;
}