#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("ubuntzei.in");
ofstream g("ubuntzei.out");
vector <pair <int,int> > v[2002];
int a[2002],MIN,MIN1,d2[2002],lim,z,d[20][2005],j,d1[2002],din[(1<<15)+1],n,m,nrp,i,x,y,c;
queue <int> q;
int main()
{
    f>>n>>m>>nrp;
    for (i=1;i<=nrp;i++)
        f>>a[i];
    for (i=1;i<=m;i++)
    {
        f>>x>>y>>c;
        v[x].push_back(make_pair(y,c));
        v[y].push_back(make_pair(x,c));
    }
    for (i=1;i<=nrp;i++)
        for (j=1;j<=n;j++)
        d[i][j]=1<<31-1;
    for (i=1;i<=nrp;i++)
    {
        q.push(a[i]);
        d[i][a[i]]=0;
        while (!q.empty())
        {
            x=q.front();
            q.pop();
            for (j=0;j<v[x].size();j++)
                if (d[i][v[x][j].first]>d[i][x]+v[x][j].second)
                    d[i][v[x][j].first]=d[i][x]+v[x][j].second,q.push(v[x][j].first);
        }
    }
    lim=1<<nrp;
    for (i=1;i<=lim;i++)
        din[i]=1<<31-1;
    for (i=0;i<=nrp-1;i++)
        din[(1<<i)]=0;
    for (i=1;i<lim;i++)
    {
        for (j=1;j<=nrp;j++)
        if (!(i & (1<<(j-1))))
        {
            for (z=1;z<=nrp;z++)
                if (i & (1<<(z-1)))
                din[(i | 1<<(j-1))]=min(din[(i | 1<<(j-1))],din[i]+d[z][a[j]]);

        }
    }
    for (i=2;i<=n;i++)
        d1[i]=1<<31-1;
    q.push(1);
    while(!q.empty())
    {
        x=q.front();
        q.pop();
        for (j=0;j<v[x].size();j++)
            if (d1[v[x][j].first]>d1[x]+v[x][j].second)
            d1[v[x][j].first]=d1[x]+v[x][j].second,q.push(v[x][j].first);
    }
    if (nrp==0) g<<d1[n];
    else
    {
        MIN1=MIN=1<<31-1;
        for (i=1;i<=n-1;i++)
            d2[i]=1<<31-1;
        q.push(n);
        while(!q.empty())
        {
            x=q.front();
            q.pop();
            for (j=0;j<v[x].size();j++)
                if (d2[v[x][j].first]>d2[x]+v[x][j].second)
                d2[v[x][j].first]=d2[x]+v[x][j].second,q.push(v[x][j].first);
        }
        for (i=1;i<=nrp;i++)
        {
            if (d1[a[i]]<MIN1) MIN1=d1[a[i]];
            if (d2[a[i]]<MIN) MIN=d2[a[i]];
        }
        g<<MIN1+MIN+din[lim-1];
    }
    return 0;
}