#include <stdio.h>
#include <algorithm>
using namespace std;
int m,n,C[2002][2002],x[2002],nod1,nod2,cost,viz[2002], d[2002], tata[2002],xyz[2000][2000],st[20],sumaminima;
void dijkstra(int x0,int x1)
{
    int i, j, minim, k, ok;
    for (i = 1; i<=n; i++)
    {
        d[i] = C[x0][i];
        tata[i] = x0;
        viz[i] = 0;
    }
    tata[x0] = 0;
    viz[x0] = 1;
    ok = 1;
    while (ok)
    {
        minim = 3500;
        for (i = 1; i<=n; i++)
        {
            if (!viz[i] && minim>d[i])
            {
                minim = d[i];
                k = i;
            }
        }
        if (minim != 3500)
        {
            viz[k] = 1;
            for (i = 1; i<=n; i++)
            {
                if (!viz[i] && d[i]>d[k]+C[k][i])
                {
                    d[i] = d[k]+C[k][i];
                    tata[i] = k;
                }
            }
        }
        else ok = 0;
    }
    for(int i=1;i<=n;++i)
    {
        xyz[x1][i] = d[i];
    }
}
int valid(int p)
{
    for(int i=1;i<p;++i)
    {
        if(st[p]==st[i])return 1;
    }
    return 0;
}
void bktr(int p)
{
    for(int i=2;i<x[0];++i)
    {
        st[p]=i;
        if(valid(p)==0)
        {
            if(p==x[0]-2)
            {
                int sumax=0;
                sumax = xyz[1][st[1]];
                for(int j=1;j<p;++j)
                {
                    sumax += xyz[st[j]][st[j+1]];
                }
                sumax += xyz[st[p]][n];
                if(sumax<sumaminima)sumaminima = sumax;
            }
            else bktr(p+1);
        }
    }
}
int main()
{
    freopen("ubuntzei.in","r",stdin);
    freopen("ubuntzei.out","w",stdout);
    scanf("%d %d %d",&n,&m,&x[0]);
    x[0]+=2;
    sumaminima = 100000;
    for(int i=1;i<=n;++i)
    {
        for(int j=1;j<=n;++j)
        {
            C[i][j]=3500;
        }
        C[i][i]=0;
    }
    x[1]=1;
    x[2]=n;
    for(int i=3;i<=x[0];++i)
    {
        scanf("%d",&x[i]);
    }
    for(int i=1;i<=m;++i)
    {
        scanf("%d %d %d",&nod1,&nod2,&cost);
        C[nod1][nod2]=cost;
        C[nod2][nod1]=cost;
    }
    /*for(int i=1;i<=n;++i)
    {
        for(int j=1;j<=n;++j)
        {
            printf("%d ",C[i][j]);
        }
        printf("\n");
    }
    printf("\n");*/
    if(x[0]==2)
    {
        sort(x+1,x+1+x[0]);
        dijkstra(1,1);
        printf("%d",d[n]);
    }
    else
    {
        for(int i=1;i<=x[0];++i)
        {
            dijkstra(x[i],i);
        }
        bktr(1);
        printf("%d",sumaminima);
    }

    /*printf("\n\n");
    for(int i=1;i<=x[0];++i)
    {
        for(int j=1;j<=n;++j)
        {
            printf("%d ",xyz[i][j]);
        }
        printf("\n");
    }*/
    return 0;
}