#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>
#define N 2010
#define PI pair<pair<int,int>,int>
#define x first.first
#define y first.second
#define cs second
#define mp make_pair
#define INF 999999999

using namespace std;

ifstream f("ubuntzei.in");
ofstream g("ubuntzei.out");

int n,i,j,m,a,b,c,d[15][N],k,C[N][N],ANS,GR[N],PR[N];
bool K[N],IQ[N];
vector<int> A[N];
queue<int> Q;
vector<PI> V;

bool Comp (PI a, PI b)
{
    return a.cs<b.cs;
}

int BF (int s)
{
    int nod,j;
    Q.push(s);
    IQ[s]=1;
    d[s][s]=0;
    while (!Q.empty())
    {
        nod=Q.front();Q.pop();
        IQ[nod]=0;
        for (j=0;j<A[nod].size();j++)
            if (d[s][nod]+C[nod][A[nod][j]]<d[s][A[nod][j]])
            {
                d[s][A[nod][j]]=d[s][nod]+C[nod][A[nod][j]];
                if (IQ[A[nod][j]]) continue;
                IQ[A[nod][j]]=1;
                Q.push(A[nod][j]);
            }
    }
}

int rad (int a)
{
    int p,b;
    for (p=a;p!=PR[p];p=PR[p]);
    for (;a!=PR[a];)
    {
        b=PR[a];
        PR[a]=p;
        a=b;
    }
    return p;
}

void unite (int a, int b)
{
    if (GR[a]>=GR[b]) PR[b]=a;
        else PR[a]=b;
    if (GR[a]==GR[b]) GR[a]++;
}

int main ()
{
    f >> n >> m;
    f >> k;
    for (i=1;i<=k;i++)
    {
        f >> a;
        K[a]=1;
    }
    for (i=0;i<15;i++)
        for (j=0;j<=n;j++) d[i][j]=INF;
    for (i=1;i<=m;i++)
    {
        f >> a >> b >> c;
        A[a].push_back(b);
        A[b].push_back(a);
        C[a][b]=C[b][a]=c;
    }
    for (i=1;i<=n;GR[i]=1,PR[i]=i,i++)
        if (K[i]==1)
            BF(i);
    /*for (i=1;i<=n;i++)
    {
        for (j=1;j<=n;j++) g << d[i][j] << ' ';
        g << '\n';
    }*/
    for (i=1;i<=n;i++)
        for (j=i+1;j<=n;j++)
        {
            if (i!=1 && i!=n && K[i]==0) continue;
            if (j!=1 && j!=n && K[j]==0) continue;
            V.push_back(mp(mp(i,j),(K[i]==1?d[i][j]:d[j][i])));
        }
    sort(V.begin(),V.end(),Comp);
    for (i=0;i<V.size();i++)
    {
        a=V[i].x;b=V[i].y;c=V[i].cs;
        if (rad(a)==rad(b)) continue;
        ANS+=c;
        unite(rad(a),rad(b));
    }
    g << ANS << '\n';
    f.close();g.close();
    return 0;
}