#include <bits/stdc++.h>
#define endl '\n'
#define int ll

using ll = long long;

constexpr int N = 2e5 + 10;
constexpr int mod = 998244353;
constexpr ll inf = 1e18;

using namespace std;

void solve(){
	int n, m, q;
	cin >> n >> m >> q;

	vector<vector<pair<int, ll>>> G(n + 1);
	vector<int> a(n + 1), d(n + 1);
	map<pair<int, int>, int> val;
	map<pair<int, int>, int> rw;
	for (int i = 1; i <= n; ++i) cin >> a[i];

	int B = sqrt(n);
	for (int i = 1; i <= m; ++i) {
		int u, v; ll w;
		cin >> u >> v >> w;
		d[u]++;
		d[v]++;
		G[u].push_back({v, w});
		G[v].push_back({u, w});
		val[{u, v}] = val[{v, u}] = w;
		rw[{u, v}] = rw[{v, u}] = w;
 	}

	vector<int> b(q);
	for (int i = 0; i < q; ++i) cin >> b[i];
	reverse(b.begin(), b.end());
	
	vector<int> sbpoint;
	for (int i = 1; i <= n; ++i) {
		if (d[i] > B) {
			sbpoint.push_back(i);
		}
 	}

 	vector<int> vis(n + 1);
	vector<ll> dp(n + 1, 0);

	vector<multiset<ll>> st(n + 1);  

	for (auto u : sbpoint) {
		for (auto [v, w] : G[u]) {
			st[u].insert(w);
		}
	}

	for (auto u : b) {
		vis[u] = 1;
		dp[u] = inf;
		if (d[u] <= B) {
			for (auto [v, w]: G[u]) {
				dp[u] = min(dp[v] + w, dp[u]);
			}
		}else {
			dp[u] = *st[u].begin();  
		}
		for (auto v : sbpoint) {
			if (val.count({v, u})) {
				st[v].extract(val[{v, u}]); 
			}
		}
		for (auto v : sbpoint) {
			if (val.count({v, u})) {
				int w = rw[{v, u}];
				st[v].insert(w + dp[u]);
				val[{v, u}] = w + dp[u];
			}
		}
	}
	ll ans = 0;
	for (int i = 1; i <= n; ++i) {
		ans = (ans + (1ll * dp[i] * a[i]) % mod) % mod;
	}
	cout << ans << endl;
}

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    //cin >> t;
    while(t--) solve();
    return 0;
}