/*

 PROB:butter

 LANG:C++

 */

 #include <iostream>

 #include <cstdio>

 #include <queue>

 #include <vector>

 using namespace std;

 const int Ni = ;

 const int INF = <<;

 struct node{

     int x,d;

     node(){}

     node(int a,int b){x=a;d=b;}

     bool operator < (const node & a) const

     {

         if(d==a.d) return x<a.x;

         else return d > a.d;

     }

 };

 vector<node> eg[Ni];

 int dis[Ni],cow[Ni],ans,p,c,n;

 void Dijkstra(int s)

 {

     int i;

     for(i=;i<=p;i++) dis[i]=INF;

     dis[s]=;

     priority_queue<node> q;

     q.push(node(s,dis[s]));

     while(!q.empty())

     {

         node x=q.top();q.pop();

         for(i=;i<eg[x.x].size();i++)

         {

             node y=eg[x.x][i];

             if(dis[y.x]>x.d+y.d)

             {

                 dis[y.x]=x.d+y.d;

                 q.push(node(y.x,dis[y.x]));

             }

         }

     }

 }

 int main()

 {

     freopen("butter.in","r",stdin);

     freopen("butter.out","w",stdout);

     ans=INF;

     scanf("%d %d %d",&n,&p,&c);

     for (int i=;i<=n;i++)

         scanf("%d",&cow[i]);

     for (int i=;i<=c;i++)

     {

         int x,y,t;

         scanf("%d %d %d",&x,&y,&t);

         //a[x][y]=t;        a[y][x]=t;

         eg[x].push_back(node(y,t));

         eg[y].push_back(node(x,t));

     }

     for (int k=;k<=p;k++)

     {

         Dijkstra(k);

         int tmp=;

         for (int i=;i<=n;i++)

             tmp+=dis[cow[i]];

         if (tmp<ans)

             ans=tmp;

     }

     printf("%d\n",ans);

     return ;

 }