#pragma GCC optimize("Ofast", "unroll-loops")
#include <bits/stdc++.h>
#pragma GCC target("avx2")
using namespace std;
#define f first
#define s second
#ifdef LOCAL
#define err cerr
#else
#define err if (0) cerr
#endif
#define data ahhhhh
const int sz = 4;
struct data {
array<pair<int, int>, 4> things = {make_pair(-1, -1), make_pair(-1, -1), make_pair(-1, -1), make_pair(-1, -1)};
bool add (pair<int, int> x) {
for (int i = 0; i < 4; i++) {
if (things[i].s == x.s) return false;
else if (!~things[i].s) {
things[i] = x;
return true;
}
}
return false;
}
bool can (int x) {
for (int i = 0; i < 4; i++) if (things[i].s == x) return false;
return !~things[3].s;
}
vector<pair<int, int>> get() {
vector<pair<int, int>> vt;
for (auto i: things) if (~i.s) vt.push_back(i);
sort(vt.begin(), vt.end());
vt.erase(vt.begin());
return vt;
}
};
signed main (signed argc, char **argv) {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int n, m, k;
cin >> n >> m >> k;
vector<vector<pair<int, int>>> adj(n);
for (int a, b, c; m--;) {
cin >> a >> b >> c;
adj[--a].push_back({--b, c});
adj[b].push_back({a, c});
}
vector<data> dt(n);
priority_queue<pair<pair<int, int>, int>, vector<pair<pair<int, int>, int>>, greater<pair<pair<int, int>, int>>> pq;
vector<bool> jh(n, 0);
for (int a; k--;) {
cin >> a;
jh[--a] = 1;
pq.push({{0, a}, a});
}
while (pq.size()) {
if (dt[pq.top().s].add(pq.top().f))
for (auto i: adj[pq.top().s]) if (dt[i.f].can(pq.top().f.s))
pq.push({{pq.top().f.f+i.s, pq.top().f.s}, i.f});
pq.pop();
}
vector<vector<pair<int, int>>> res;
vector<pair<int, pair<int, int>>> lst;
for (int i = 0; i < n; i++) if (jh[i]) {
res.push_back(dt[i].get());
for (auto j: res.back()) if (i < j.s) lst.push_back({j.f, {i, j.s}});
} else res.push_back({});
sort(lst.begin(), lst.end());
int ans = lst[0].f;
auto unq = [&](vector<int> v) { sort(v.begin(), v.end()); return unique(v.begin(), v.end()) == v.end();};
for (int i = 1; i < n; i++) if (unq({lst[0].s.f, lst[0].s.s, lst[i].s.f, lst[i].s.s})) {
ans += lst[i].f;
break;
}
for (auto i: res[lst[0].s.f]) for (auto j: res[lst[0].s.s])
if (unq({lst[0].s.f, lst[0].s.s, i.s, j.s})) ans = min(ans, i.f+j.f);
cout << ans << "\n";
}
/*
*
* ┏┓ ┏┓+ +
* ┏┛┻━━━┛┻┓ + +
* ┃ ━ ┃ ++ + + +
* ████━████+
* ◥██◤ ◥██◤ +
* ┃ ┻ ┃
* ┗━┓ ┏━┛ + +
* ┃ ┃ + + + +Code is far away from
* ┃ ┃ + bug with the llama protecting
* ┃ ┗━━━┓ 神兽保佑,代码无bug
* ┃ ┣┓
* ┃ ┏┛
* ┗┓┓┏━┳┓┏┛ + + + +
* ┃┫┫ ┃┫┫
* ┗┻┛ ┗┻┛+ + + +
*/
//thanks cindy
