#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define int long long
#define all(x) (x).begin(), (x).end()
typedef long double ld;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<bool>> vvb;
typedef vector<vector<ll>> vvll;
typedef vector<string> vs;
typedef vector<vector<string>> vvs;
typedef vector<char> vc;
typedef vector<vector<char>> vvc;
typedef map<int, int> mii;
typedef unordered_map<int, int> umii;
const int mod = 1e9 + 7;
const int inf = INTMAX_MAX;
const bool tc = false;
int n, m, k;
const int mxn = 1e5 + 1;
vector<pii> adj[mxn]; int a[mxn];
vi sp;
struct dijk {
int n, s, d;
bool operator<(const dijk &other) const {
if (d != other.d) return d < other.d;
if (n != other.n) return n < other.n;
return s < other.s;
}
};
pair<int, pii> comp(vi &active, vi &vis) {
// find all special nodes
sp.clear(); vi dist(n, 1e18); vi src(n);
set<dijk> dk; vis.assign(n, 0);
for (int i = 0; i < n; i++) {
if (!a[i]) continue;
if (!active[i]) continue;
dijk tmp;
tmp.n = i;
tmp.s = i;
tmp.d = 0;
dk.insert(tmp);
sp.pb(i);
//cout << "added " << i + 1 << " to start\n";
}
while (dk.size()) {
auto cur = *dk.begin();
dk.erase(dk.begin());
// finalize ONLY if cur.s != cur.n
if (cur.s != cur.n) {
if (vis[cur.n]) continue; // already finalized from some other source
vis[cur.n] = 1;
src[cur.n] = cur.s;
dist[cur.n] = cur.d; // finalize distance from the other source
}
// else (cur.s == cur.n): do NOT mark visited;
// let other sources reach this node later.
for (auto &neighbour : adj[cur.n]) {
if (cur.s == neighbour.fi) continue; // avoid pairing with itself
if (cur.d + neighbour.se < dist[neighbour.fi]) {
dk.erase({neighbour.fi, src[neighbour.fi], dist[neighbour.fi]});
dist[neighbour.fi] = cur.d + neighbour.se;
src[neighbour.fi] = cur.s;
dk.insert({neighbour.fi, cur.s, dist[neighbour.fi]});
}
}
}
// for (auto &x : dist) cout << x << ' ';
// cout << '\n';
// for (auto &x : src) cout << x + 1 << ' ';
// cout << '\n';
pair<int, pii> ans = {(int)1e18, {(int)-1, (int)-1}};
for (auto &i : sp) ans = min(ans, {dist[i], {i, src[i]}});
return ans;
}
pair<int, pii> find(vi &active) {
vi v(n);
return comp(active, v);
}
inline void solve() {
cin >> n >> m >> k;
for (int i = 0; i < m; i++) {
int u, v, w;
cin >> u >> v >> w;
u--; v--;
adj[u].pb({v, w});
adj[v].pb({u, w});
}
for (int i = 0; i < k; i++) {
int x; cin >> x; x--;
a[x] = 1;
}
vi active(n, 1);
pair<int, pii> f = find(active);
active[f.se.fi] = 0;
active[f.se.se] = 0;
pair<int, pii> s = find(active);
// cout << f.fi << " " << f.se.fi + 1 << " " << f.se.se + 1 << '\n';
// cout << s.fi << " " << s.se.fi + 1 << " " << s.se.se + 1 << '\n';
assert(f.fi + s.fi < 1e18);
cout << f.fi + s.fi << '\n';
}
void setIO(string s) {
freopen((s + ".in").c_str(), "r", stdin);
freopen((s + ".out").c_str(), "w", stdout);
}
signed main() {
ios::sync_with_stdio(false);
cout.tie(0);
cin.tie(0);
//setIO();
int t = 1;
if (tc) {
cin >> t;
}
while (t--) {
solve();
}
}
