#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(v) (v).begin(), (v).end()
template<typename T> bool ckmn(T& a, const T& b){
if(a > b)
return a = b, true;
return false;
}
const int N = 1e5 + 5, M = 3e6 + 5, INF = 1e9;
/*
minimum distance = (a,b)
{x1, y1} != (a) and (b) -> optimal to choose (a,b)
{(a), y1} != (b) -> if we choose {x2, y2} != (a) and (b) we should choose (a,b)
-> we have to choose {(b), y2}
*/
struct Edge{
int u,v,w;
Edge(int u = 0, int v = 0, int w = 0): u(u), v(v), w(w) {}
};
int n, m, k, dist[N], near[N];
bool special[N]; Edge E[M];
vector<int> adj[N];
void dijkstra(){
priority_queue<pair<int,int>> pq;
for(int i = 1; i <= n; i++){
if(special[i]) pq.push(make_pair(0, i));
}
while(!pq.empty()){
pair<int,int> e = pq.top(); pq.pop();
int x = e.second, cur_dist = -e.first;
if(cur_dist > dist[x]) continue;
for(int id : adj[x]){
int v = E[id].u ^ E[id].v ^ x, w = E[id].w;
if(ckmn(dist[v], dist[x] + w)){
near[v] = near[x];
pq.push(make_pair(-dist[v], v));
}
}
}
}
void solve()
{
cin >> n >> m >> k;
for(int i = 0; i < m; i++){
int u,v,w; cin >> u >> v >> w;
E[i] = Edge(u, v, w);
adj[u].pb(i), adj[v].pb(i);
}
for(int i = 0; i < k; i++){
int x; cin >> x;
special[x] = true;
}
auto reset = [&]() -> void{
for(int i = 1; i <= n; i++){
if(special[i]) dist[i] = 0, near[i] = i;
else dist[i] = INF, near[i] = 0;
}
};
reset(), dijkstra();
int opt1 = -1, opt2 = -1, cdist = INF;
for(int i = 0; i < m; i++){
int u = E[i].u, v = E[i].v, w = E[i].w;
if(near[u] == near[v]) continue;
if(ckmn(cdist, dist[u] + dist[v] + w)){
opt1 = near[u];
opt2 = near[v];
}
}
special[opt1] = special[opt2] = false;
// cout << "FOUND OPT: " << opt1 <<" " << opt2 << "\n";
reset(), dijkstra();
int answer = INF;
for(int i = 0; i < m; i++){
int u = E[i].u, v = E[i].v, w = E[i].w;
if(near[u] == near[v]) continue;
ckmn(answer, cdist + dist[u] + dist[v] + w);
}
vector<int> MnOpt1(n + 1, INF);
special[opt1] = true; reset(), dijkstra();
for(int i = 0; i < m; i++){
int u = E[i].u, v = E[i].v, w = E[i].w;
if(near[u] == near[v]) continue;
if(near[u] == opt1 || near[v] == opt1){
int target = (near[u] == opt1 ? near[v] : near[u]);
ckmn(MnOpt1[target], dist[u] + dist[v] + w);
}
}
special[opt1] = false;
vector<int> MnOpt2(n + 1, INF);
special[opt2] = true; reset(), dijkstra();
for(int i = 0; i < m; i++){
int u = E[i].u, v = E[i].v, w = E[i].w;
if(near[u] == near[v]) continue;
if(near[u] == opt2 || near[v] == opt2){
int target = (near[u] == opt2 ? near[v] : near[u]);
ckmn(MnOpt2[target], dist[u] + dist[v] + w);
}
}
vector<int> idx1(n + 1, 0), idx2(n + 1, 0);
for(int i = 1; i <= n; i++) idx1[i] = idx2[i] = i;
sort(1 + all(idx1), [&](int x, int y){return MnOpt1[x] < MnOpt1[y];});
sort(1 + all(idx2), [&](int x, int y){return MnOpt2[x] < MnOpt2[y];});
int last_dist1 = MnOpt1[idx1[1]] + MnOpt2[(idx1[1] == idx2[1] ? idx2[2] : idx2[1])];
int last_dist2 = MnOpt2[idx2[1]] + MnOpt1[(idx2[1] == idx1[1] ? idx1[2] : idx1[1])];
answer = min(answer, min(last_dist1, last_dist2));
cout << answer << "\n";
}
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
#define name "InvMOD"
if(fopen(name".INP", "r")){
freopen(name".INP", "r", stdin);
freopen(name".OUT", "w", stdout);
}
solve();
return 0;
}
