#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <array>
#include <stack>
#include <queue>
#include <random>
#include <numeric>
#include <functional>
#include <chrono>
#include <utility>
#include <iomanip>
#include <assert.h>
using namespace std;
void dbg_out() { cerr << endl; }
template<typename Head, typename... Tail>
void dbg_out(Head H, Tail... T) { cerr << ' ' << H; dbg_out(T...); }
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#define rng_init mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define rng_seed(x) mt19937 rng(x)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int) (x).size()
// #define int long long
const int MXN = 1e5 + 5, INF = 1e9 + 5;
int N, M, K;
int par[MXN];
vector<pair<int, int>> g[MXN];
vector<array<int, 3>> edges;
vector<int> dijkstra(const vector<int> &src) {
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<>> pq;
vector<int> dist(N, INF);
for (int i = 0; i < N; i++)
par[i] = i;
for (const auto &x : src) {
dist[x] = 0;
pq.emplace(0, x);
}
while (!pq.empty()) {
auto cur = pq.top();
pq.pop();
int u = cur.second, cur_dist = cur.first;
if (cur_dist != dist[u]) continue;
for (const auto &[v, wt] : g[u]) {
int new_dist = cur_dist + wt;
if (new_dist < dist[v]) {
dist[v] = new_dist;
pq.emplace(new_dist, v);
par[v] = par[u];
}
}
}
return dist;
}
array<int, 3> best_pair(const vector<int> &dist) {
pair<int, int> points = {-1, -1};
int points_dist = INF;
for (const auto &[u, v, w] : edges) {
if (par[u] == par[v]) continue;
int cur_dist = dist[u] + dist[v] + w;
if (cur_dist < points_dist) {
points.first = par[u];
points.second = par[v];
points_dist = cur_dist;
}
}
return array<int, 3>{points.first, points.second, points_dist};
}
void solve() {
cin >> N >> M >> K;
for (int i = 0; i < M; i++) {
int u, v, w;
cin >> u >> v >> w;
u--, v--;
edges.push_back({u, v, w});
g[u].emplace_back(v, w);
g[v].emplace_back(u, w);
}
vector<int> special(K);
for (auto &x : special) {
cin >> x;
x--;
}
vector<int> dist_special = dijkstra(special);
array<int, 3> points1 = best_pair(dist_special);
vector<int> special_new;
for (const auto &x : special) {
if (x == points1[0] || x == points1[1]) continue;
special_new.push_back(x);
}
vector<int> dist_special_new = dijkstra(special_new);
array<int, 3> points2 = best_pair(dist_special_new);
int ans = points1[2] + points2[2];
vector<int> dist1 = dijkstra(vector<int>{points1[0]});
vector<int> dist2 = dijkstra(vector<int>{points1[1]});
set<pair<int, int>> dist2_set;
for (const auto &i : special) {
if (i == points1[0] || i == points1[1]) continue;
dist2_set.insert({dist2[i], i});
}
for (const auto &i : special) {
if (i == points1[0] || i == points1[1]) continue;
dist2_set.erase({dist2[i], i});
pair<int, int> dist2_best = *dist2_set.begin();
dist2_set.insert({dist2[i], i});
ans = min(ans, dist1[i] + dist2_best.first);
}
cout << ans;
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int TC = 1;
// cin >> TC;
while (TC--) solve();
}
