#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <algorithm>
#define nmax 2005
using namespace std;
ifstream f("ubuntzei.in");
ofstream g("ubuntzei.out");
int n,m, k, a[nmax][nmax], sol[20];
int mn=1e9, dist;
vector <int> c;

void citire()
{
    int i,j,x,y,cs;
    f>>n>>m;
    f>>k;
    c.push_back(1);
    for(i=1; i<=k; i++)
    {
        f>>x; c.push_back(x);
    }
    c.push_back(n);
    for(i=1; i<=m; i++)
    {
        f>>x>>y>>cs;
        a[x][y]=cs; a[y][x]=cs;
    }
    for(i=1; i<=n; i++)
    for(j=1; j<=n; j++)
        if(a[i][j]==0)
        a[i][j]=1e9;
}

int continuare(int p)
{
    int i,ok=1;
    for(i=1; i<=p-1; i++)
        if(sol[i]==sol[p])
            ok=0;
    return ok;
}

void bk(int p)
{
    int val,i,j;
    for(i=1; i<c.size()-1; i++)
    {
        val=c[i];
        sol[p]=val;
        if(continuare(p)==1)
        if(p==k)
        {
            dist=a[1][sol[1]];
            for(j=1; j<=k; j++)
                dist+=a[sol[j-1]][sol[j]];
            dist=dist+a[sol[k]][n];
            if(dist<mn)
                mn=dist;
        }
        else
            bk(p+1);
    }
}

int main()
{
    citire();
    int i,j,o, nod, cst;
    for(o=1; o<=n; o++)
      for(i=1; i<=n; i++)
        for(j=1; j<=n; j++)
    {
        if(a[i][j]>a[o][j]+a[i][o])
        {
            a[i][j]=a[o][j]+a[i][o];
            a[j][i]=a[o][j]+a[i][o];
        }
    }
    /*if(k==0)
        g<<a[1][n];
    else
    {bk(1); g<<mn;}*/

    if(k==0)
        g<<a[1][n];
    else
    {
        sort(c.begin(), c.end());
        do
        {
            dist=0;
        for(i=1; i<c.size(); i++)
             dist+=a[c[i-1]][c[i]];
            if(mn>dist)
                mn=dist;
        }while(next_permutation(c.begin()+1, c.end()-1));
    g<<mn;
    }
    f.close();
    g.close();
    return 0;
}