#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
#define int long long
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ppb pop_back
#define eb emplace_back
#define g0(a) get<0>(a)
#define g1(a) get<1>(a)
#define g2(a) get<2>(a)
#define g3(a) get<3>(a)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef double db;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
int N, M, K, ans = 1e16, dist[100005], ddist[100005], st[100005];
bool yes[100005];
iii ed[3000005];
vector<ii> adj[100005];
priority_queue<iii, vector<iii>, greater<iii> > pq2;
priority_queue<ii, vector<ii>, greater<ii> > pq;
pair<int, ii> shortest_pair() {
int fp = 1e16;
ii fpp;
for (int i = 1; i <= N; i++) {
if (yes[i]) {
dist[i] = 0;
st[i] = i;
pq2.emplace(0, i, i);
} else {
dist[i] = 1e16;
st[i] = -1;
}
}
while (!pq2.empty()) {
auto [d, u, stt] = pq2.top();
pq2.pop();
if (d != dist[u]) continue;
for (auto v : adj[u])
if (dist[v.first] > d + v.second) {
dist[v.first] = d + v.second;
st[v.first] = stt;
pq2.emplace(dist[v.first], v.first, stt);
}
}
for (int i = 1, u, v, w; i <= M; i++) {
tie(u, v, w) = ed[i];
if (st[u] != -1 && st[u] != st[v] && dist[u] + dist[v] + w < fp) {
fp = dist[u] + dist[v] + w;
fpp = mp(st[u], st[v]);
}
}
return mp(fp, fpp);
}
void dijk(int s) {
for (int i = 1; i <= N; i++)
if (i == s) ddist[i] = 0;
else ddist[i] = 1e16;
pq.emplace(0, s);
while (!pq.empty()) {
auto [d, u] = pq.top();
pq.pop();
if (d != ddist[u]) continue;
for (auto v : adj[u])
if (ddist[v.first] > d + v.second) {
ddist[v.first] = d + v.second;
pq.emplace(ddist[v.first], v.first);
}
}
}
main() {
ios::sync_with_stdio(0);
cin.tie(0);
cin >> N >> M >> K;
for (int i = 1, u, v, w; i <= M; i++) {
cin >> u >> v >> w;
adj[u].eb(v, w);
adj[v].eb(u, w);
ed[i] = mt(u, v, w);
}
for (int i = 1, x; i <= K; i++) {
cin >> x;
yes[x] = 1;
}
auto f = shortest_pair();
yes[f.second.first] = yes[f.second.second] = 0;
auto s = shortest_pair();
ans = min(ans, f.first + s.first);
yes[f.second.first] = yes[f.second.second] = 1;
dijk(f.second.first);
for (int i = 1; i <= N; i++)
if (yes[i] && i != f.second.first && i != f.second.second) s = min(s, mp(ddist[i], mp(f.second.first, i)));
dijk(f.second.second);
for (int i = 1; i <= N; i++)
if (yes[i] && i != f.second.first && i != f.second.second) s = min(s, mp(ddist[i], mp(f.second.second, i)));
if (f.second.first != s.second.first && f.second.first != s.second.second && f.second.second != s.second.first && f.second.second != s.second.second) ans = min(ans, f.first + s.first);
else {
int fff, sss, common;
yes[s.second.first] = yes[s.second.second] = 0;
auto ff = shortest_pair();
ans = min(ans, ff.first + s.first);
yes[s.second.first] = yes[s.second.second] = 1;
for (int x : {f.second.first, f.second.second})
if (x == s.second.first || x == s.second.second) common = x;
for (int x : {f.second.first, f.second.second})
if (x != common) fff = x;
for (int x : {s.second.first, s.second.second})
if (x != common) sss = x;
yes[fff] = yes[sss] = 0;
auto ffff = shortest_pair();
dijk(fff);
ans = min(ans, ffff.first + ddist[sss]);
yes[fff] = yes[sss] = 1;
}
cout << ans << '\n';
}
