#include <cstdio>

#define NMax 2001
#define INF 0x3f3f3f3f
using namespace std;

int city_nr,mx,n,m,k,x,y,c;
int st[NMax],city[NMax],fol[NMax];
int dist[NMax][NMax],a[NMax][NMax];

void rf(){

    for(int inter = 1; inter <= n; ++inter){
        for(int i = 1; i <= n; ++i){
            for(int j = 1; j <= n; ++j){
                if(dist[i][j] > dist[i][inter] + dist[inter][j]){
                    dist[i][j] = dist[i][inter] + dist[inter][j];
                }
            }
        }
    }
}
void back(int nivel){
    for(int i = 1; i <= k; i++){
        if(fol[i] == 0){
            fol[i] = 1;
            st[nivel] = i;

            int da = 1;
            if(da == 1){
                if(nivel == k){
                    int s = 0;
                    s += dist[1][city[st[1]]];
                    for(int j = 2; j <= k; j++){
                        s += dist[city[st[j]]][city[st[j - 1]]];
                    }
                    s += dist[n][city[st[k]]];
                    if(s > mx)
                        mx = s;
                }
                else
                    back(k + 1);
            }
            fol[i] = 0;
        }
    }
}
int main()
{
    freopen("ubuntzei.in","r",stdin);
    freopen("ubuntzei.out","w",stdout);
    scanf("%d%d%d",&n,&m,&k);
    printf("%f\n",1.0*(sizeof(a) + sizeof(dist) + sizeof(city) + sizeof(fol) + sizeof(st))/1024/1024);
    for(int i = 1; i <= k; ++i){
        scanf("%d",&x);
        city[++city_nr] = x;
    }

    for(int i = 1; i <= m; ++i){
        scanf("%d%d%d",&x,&y,&c);
        a[x][y] = c;
        a[y][x] = c;
    }
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= n; ++j){
            if(a[i][j] == 0 && i != j){
                dist[i][j] = INF;
            }else{
                dist[i][j] = a[i][j];
            }
        }
    }
    rf();
    back(1);
    printf("%d",mx);
    return 0;
}