#include <bits/stdc++.h>
#define pii pair<int,int>
using namespace std;
ifstream in("ubuntzei.in");
ofstream out("ubuntzei.out");
const int N = 10005;
const int K = 20;
vector< pair<int,int> >v[N];
int dp[K][1<<K],cost[N][N],a[K];
bool viz[N];
void dijkstra(int x)
{
    memset(viz,0,sizeof(viz));
    cost[x][x] = 0;
    priority_queue< pii,vector<pii>,greater<pii> > q;
    q.push({0,x});
    while (!q.empty())
    {
        int now = q.top().second;
        q.pop();
        if (viz[now])
            continue;
        viz[now] = 1;
        for (auto it: v[now])
        {
            int next = it.first, c = it.second;
            if (cost[x][next]>cost[x][now]+c)
            {
                cost[x][next]=cost[x][now]+c;
                q.push({cost[x][next],next});
            }
        }
    }
}
int main()
{
    int n,m,k;
    in >> n >> m >> k;
    k+=2;
    a[0] = 1;
    a[k-1] = n;
    for (int i = 1; i<k-1; i++)
        in >> a[i];
    for (int i = 0; i<k; i++)
        viz[a[i]] = 1;
    for (int i = 1; i<=m; i++)
    {
        int x,y,c;
        in >> x >> y >> c;
        v[x].push_back({y,c});
        v[y].push_back({x,c});
    }
    for (int i = 1; i<=n; i++)
        for (int j = 1; j<=n; j++)
            cost[i][j] = INT_MAX;
    for (int i = 0; i<k; i++)
        dijkstra(a[i]);
    for (int j = 0; j<k; j++)
        for (int i = 1; i<(1<<k); i++)
            dp[j][i] = INT_MAX;
    for (int i = 0; i<k; i++)
        dp[i][1<<i] = cost[1][a[i]];
    for (int i = 1; i<(1<<k); i++)
        for (int j = 0; j<k; j++)
            if ((1<<(j))&i)
            {
                for (int z = 0; z<k; z++)
                    if (!((1<<(z))&i))
                        dp[z][i^(1<<(z))] = min(dp[z][i^(1<<(z))],dp[j][i]+cost[a[j]][a[z]]);
            }
    out << dp[k-1][(1<<k)-1];
}