#include <bits/stdc++.h>
using namespace std;
struct DSU {
int n;
vector<int> p, r;
DSU(int n=0){ init(n); }
void init(int n_){
n = n_;
p.resize(n+1);
r.assign(n+1,0);
for(int i=1;i<=n;i++) p[i]=i;
}
int find(int x){ return p[x]==x?x:p[x]=find(p[x]); }
bool unite(int a,int b){
a = find(a); b = find(b);
if(a==b) return false;
if(r[a]<r[b]) swap(a,b);
p[b]=a;
if(r[a]==r[b]) r[a]++;
return true;
}
};
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, k, m;
if(!(cin >> n >> k >> m)) return 0;
vector<int> special(k);
vector<char> is_special(n+1, 0);
for(int i=0;i<k;i++){
cin >> special[i];
is_special[special[i]] = 1;
}
struct Edge { int u,v; long long w; };
vector<Edge> edges;
edges.reserve(m);
for(int i=0;i<m;i++){
int u,v; long long w;
cin >> u >> v >> w;
edges.push_back({u,v,w});
}
// Kruskal: build MST adjacency
sort(edges.begin(), edges.end(), [](const Edge &a, const Edge &b){ return a.w < b.w; });
DSU dsu(n);
dsu.init(n);
vector<vector<pair<int,long long>>> adj(n+1);
int taken = 0;
for(auto &e : edges){
if(dsu.unite(e.u, e.v)){
adj[e.u].push_back({e.v, e.w});
adj[e.v].push_back({e.u, e.w});
taken++;
if(taken == n-1) break;
}
}
if(k <= 1){
cout << 0 << '\n';
return 0;
}
// Root the tree at any special node (take special[0])
int root = special[0];
vector<int> parent(n+1, -1);
vector<long long> pedge(n+1, 0); // weight of edge to parent
vector<int> order; order.reserve(n);
// iterative stack DFS to build parent+order (postorder)
stack<int> st;
st.push(root);
parent[root] = 0; // mark visited, parent 0
while(!st.empty()){
int u = st.top(); st.pop();
order.push_back(u);
for(auto [v,w] : adj[u]){
if(parent[v] == -1){
parent[v] = u;
pedge[v] = w;
st.push(v);
}
}
}
// order currently is preorder (stack-based), we need postorder -> reverse it
reverse(order.begin(), order.end());
// cnt[u] = number of special nodes in subtree u
vector<int> cnt(n+1, 0);
for(int i=1;i<=n;i++) if(is_special[i]) cnt[i]=1;
long long ans = 0;
for(int u : order){
if(u == root) continue;
// u has parent parent[u], edge weight pedge[u]
if(cnt[u] > 0 && cnt[u] < k){
// this edge is necessary to connect specials on both sides
ans += pedge[u];
}
// push counts up
cnt[parent[u]] += cnt[u];
}
cout << ans << '\n';
return 0;
}
