#include <bits/stdc++.h>
#define int long long
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]: ", print_args(__VA_ARGS__)
template <class... T>
void print_args(T... args) { ((cerr << args << ' '), ...) << '\n'; }
using u32 = unsigned;
using u64 = unsigned long long;
using i64 = long long;
using i128 = __int128_t;
const int mod = 998244353;
const int MAXN = 1e5 + 10;
int n, m, q;
int a[MAXN], b[MAXN], deg[MAXN], dp[MAXN];
multiset<int> st[MAXN];
vector<pii> g[MAXN];
void solve() {
    cin >> n >> m >> q;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    for (int i = 1; i <= m; i++) {
        int u, v, w;
        cin >> u >> v >> w;
        deg[u]++, deg[v]++;
        g[u].push_back({v, w});
        g[v].push_back({u, w});
    }
    for (int i = 1; i <= q; i++) {
        cin >> b[i];
    }
    dp[b[q]] = 1e18;
    int B = sqrt(n + 1);
    for (int i = 1; i <= n; i++) {
        if (deg[i] > B) { // 不超过2m/B个
            for (auto [j, w] : g[i]) {
                st[i].insert(dp[j] + w);
            }
        }
    }
    /*
    dp：时间i之前在u点，i时刻离开u点，并且在之后的时间都安全的后缀最小值
    如果下一秒这个地方被砸，那么u点一定转移到相邻的点最优
    dp[i - 1][j] <- dp[i][j]
    dp[i - 1][j] <- dp[i][k](k是j的邻居)
    */
    for (int i = q; i; i--) {
        int u = b[i];
        int pre = dp[u];
        int res = 1e18;
        if (deg[u] <= B) { // 度 <= sqrt(n)，那么可以暴力枚举邻居，更新权值
            for (auto [v, w] : g[u]) {
                res = min(res, dp[v] + w);
            }
            for (auto [v, w] : g[u]) {
                if (deg[v] > B) {
                    st[v].erase(st[v].find(pre + w));
                    st[v].insert(res + w);
                }
            }
        } else {
            res = min(res, *st[u].begin());
        }
        dp[u] = res;
    }
    int ans = 0;
    for (int i = 1; i <= n; i++) {
        ans += dp[i] * a[i] % mod;
        ans %= mod;
    }
    cout << ans << '\n';
}
signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int _ = 1;
    // cin >> _;
    while (_--) {
        solve();
    }
    return 0;
}