#include <bits/stdc++.h>
#define dim 2002
using namespace std;
ifstream fin ("ubuntzei.in");
ofstream fout("ubuntzei.out");
int n,k,put[22],ord[dim],Sol[18][131073],sol[dim];
const int inf=2000000000;

struct el
{
    int nod,cost,st;
    bool operator < (const el &A) const
    {
        return cost>A.cost;
    }
};
priority_queue<el> pq;
vector<el> a[dim],aa[dim];


void dijkstra ()
{
    int i,j;
    for (i=1; i<=k; i++)
        for (j=1; j<=put[k]-1; ++j)
            Sol[i][j]=inf;
    Sol[1][1]=0;
    pq.push({1,0,1});
    while (!pq.empty())
    {
        el x=pq.top();
        pq.pop();
        if (x.cost==Sol[x.nod][x.st])
            for (auto y: aa[x.nod])
                if((x.st&put[y.nod-1])!=0 && x.cost+y.cost<Sol[y.nod][x.st])
                {
                    Sol[y.nod][x.st]=x.cost+y.cost;
                    pq.push({y.nod,Sol[y.nod][x.st],x.st});
                }
                else     if((x.st&put[y.nod-1])==0&&x.cost+y.cost<Sol[y.nod][x.st|put[y.nod-1]])
                {
                    Sol[y.nod][x.st|put[y.nod-1]]=x.cost+y.cost;
                    pq.push({y.nod,x.cost+y.cost,x.st|put[y.nod-1]});
                }
    }
    fout<<Sol[k][put[k]-1];
}

void dijk ()
{
    while (!pq.empty())
    {
        el x=pq.top();
        pq.pop();
        if (x.cost==sol[x.nod])
            for (auto y: a[x.nod])
                if (x.cost+y.cost<sol[y.nod])
                {
                    sol[y.nod]=x.cost+y.cost;
                    pq.push({y.nod,sol[y.nod]});
                }
    }
}

int32_t main()
{
    int i,j,m,x,y,z;
    fin>>n>>m>>k;
    put[0]=1;
    for (i=1; i<=20; i++)
        put[i]=put[i-1]*2;
    for (i=1; i<=k; i++)
        fin>>ord[i];
    ord[++k]=1;
    ord[++k]=n;
    sort(ord+1,ord+k+1);
    for (i=1; i<=m; i++)
    {
        fin>>x>>y>>z;
        a[x].push_back({y,z,0});
        a[y].push_back({x,z,0});
    }
    for (i=1; i<=k; i++)
    {
        for (j=1; j<=n; j++)
            sol[j]=inf;
        sol[ord[i]]=0;
        pq.push ({ord[i],0});
        dijk();
        for (j=1; j<=k; j++)
            if (i!=j && sol[ord[j]]!=inf)
                aa[i].push_back({j,sol[ord[j]],0});
    }
    dijkstra();
    return 0;
}