#include <fstream>
#include <vector>
#include <queue>

using namespace std;

ifstream in ("gather.in");
ofstream out ("gather.out");

struct str{
    int y, d, c;
};
/// in dijkstra, y = nod curent

const int max_size1 = 751, max_size2 = 20, INF = 1e9 + 1;

int dp[max_size1][max_size2], dt[max_size1], n, k;

vector <str> mc[max_size1];
queue <str> q;

void djk ()
{
    int ct, dist;
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= k; j++)
        {
            dp[i][j] = INF;
        }
    }
    dp[1][1] = 0;
    q.push({1, 0, 1});
    while (!q.empty())
    {
        str nod = q.front();
        q.pop();
        for (auto f : mc[nod.y])
        {
            if (nod.c  - 1 <= f.c)
            {
                ct = nod.c;
                if (dt[f.y] == 1)
                {
                    ct++;
                }
                dist = nod.d + f.d * ct;
                if (dp[f.y][ct] > dist)
                {
                    dp[f.y][ct] = dist;
                    q.push({f.y, dist, ct});
                }
            }
        }
    }
}

int main ()
{
    int m;
    in >> k >> n >> m;
    for (int i = 1; i <= k; i++)
    {
        int x;
        in >> x;
        dt[x] = 1;
    }
    while (m--)
    {
        int x, y, d, c;
        in >> x >> y >> d >> c;
        mc[x].push_back({y, d, c});
        mc[y].push_back({x, d, c});
    }
    djk();
    int ans = INF;
    for (int i = 1; i <= n; i++)
    {
        ans = min(ans, dp[i][k]);
    }
    out << ans;
    in.close();
    out.close();
    return 0;
}