#include<cstdio>
#include<vector>
#include<queue>
using namespace std;
const int INF=0x7fffffff;
const int MAXN=2050;
const int MAXM=10050;
const int MAXK=(1<<17)+5;

struct DRUM
{
    int cost,fiu;
};
struct NOD
{
    int nod,goal;
};

int important[MAXN],cost[25][MAXK],tcost[20][MAXN];
int best[20][20];
bool inqueue[MAXN][MAXK];
vector <DRUM> drum[MAXN];
vector <int> vip;
NOD tata,fiu;
queue <NOD> q;
bool iq[MAXK + 1],viz[MAXK + 1];
int main()
{
    int n,m,k,i,j;
    freopen("ubuntzei.in","r",stdin);
    freopen("ubuntzei.out","w",stdout);
    scanf("%d%d",&n,&m);
    scanf("%d",&k);
    int cnt=0;
    for(i=1;i<=k;i++)
    {
        scanf("%d",&j);
        important[j]=i;
        vip.push_back(j);
    }
    if(important[1]==0)
    {
        important[1]=k+1;
        k++;
        vip.push_back(1);
    }
    if(important[n]==0)
    {
        important[n]=k+1;
        k++;
        vip.push_back(n);
    }
    int x,y,c;
    DRUM temp;
    for(i=1;i<=m;i++)
    {
        scanf("%d%d%d",&x,&y,&c);
        temp.fiu=x;
        temp.cost=c;
        drum[y].push_back(temp);
        temp.fiu=y;
        drum[x].push_back(temp);
    }

    for(i=0;i<=k;i++)
        for(j=0;j<=n;j++)
            tcost[i][j]=INF;

    for(i=1;i<=2000&&cnt<=k;i++)
        if(important[i])
        {
            cnt++;
            tata.nod=i;
            q.push(tata);
            tcost[cnt][tata.nod]=0;
            iq[tata.nod]=1;
            while(!q.empty())
            {
                tata=q.front();
                //printf("%d\n",tata.nod);
                q.pop();
                iq[tata.nod]=0;
                if(important[tata.nod]&&tata.nod!=i)
                {
                    best[i][tata.nod]=tcost[cnt][tata.nod];
                }
                for(j=0;j<drum[tata.nod].size();j++)
                {
                    fiu.nod=drum[tata.nod][j].fiu;
                    if(tcost[cnt][tata.nod]+drum[tata.nod][j].cost<tcost[cnt][fiu.nod])
                    {
                        tcost[cnt][fiu.nod]=tcost[cnt][tata.nod]+drum[tata.nod][j].cost;
                        if(iq[fiu.nod]==0)
                        {
                            iq[fiu.nod]=1;
                            q.push(fiu);
                        }
                    }
                }
            }
            //printf("\n\n");
        }
    ///*
    int lim=1<<k;
    for(i=0;i<=18;i++)
        for(j=0;j<lim;j++)
            cost[i][j]=INF;
    tata.nod=1;
    tata.goal=1<<(important[1]-1);
    q.push(tata);
    inqueue[tata.nod][tata.goal]=true;
    cost[important[tata.nod]][tata.goal]=0;
    while(!q.empty())
    {
        //printf("%d %d\n",tata.nod,tata.goal);
        tata=q.front();
        q.pop();
        inqueue[tata.nod][tata.goal]=false;
        for(i=0;i<vip.size();i++)
        {
            if(vip[i]==tata.nod)
                continue;
            fiu.goal=tata.goal;
            fiu.nod=vip[i];
            if(important[fiu.nod]<=k)
            {
                fiu.goal|=1<<(important[fiu.nod]-1);
            }
            if(cost[important[tata.nod]][tata.goal]+best[tata.nod][fiu.nod]<cost[important[fiu.nod]][fiu.goal])
            {
                cost[important[fiu.nod]][fiu.goal]=cost[important[tata.nod]][tata.goal]+best[tata.nod][fiu.nod];
                if(inqueue[fiu.nod][fiu.goal]==false)
                {
                    inqueue[fiu.nod][fiu.goal]=true;
                    q.push(fiu);
                }
            }
        }
    }
    printf("%d",cost[important[n]][(1<<k)-1]);//*/
    return 0;
}