#pragma GCC optimize("Ofast,inline,unroll-loops,fast-math,no-stack-protector")
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 7;
const int mod = 998244353;
const ll inf = 1e15;
using pii = pair<ll, ll>;
vector<pii> g[N];
void solve()
{
    int n, m, q;
    cin >> n >> m >> q;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i];
    }
    vector<int> du(n + 1);
    vector<array<int, 3>> edge;
    map<pii, int> mp;
    for (int i = 1; i <= m; i++)
    {
        int u, v, w;
        cin >> u >> v >> w;
        if (u > v)
            swap(u, v);
        if (mp.count({u, v}))
        {
            mp[{u, v}] = min(w, mp[{u, v}]);
        }
        else
        {
            mp[{u, v}] = w;
        }
    }
    for (auto [pi, w] : mp)
    {
        auto [u, v] = pi;
        edge.push_back({u, v, w});
        du[u]++, du[v]++;
    }
    for (auto [u, v, w] : edge)
    {
        if ((du[u] == du[v] && u > v) || du[u] > du[v])
        {
            swap(u, v);
        }
        g[u].push_back({v, w});
        // du[v]++;
    }
    du.assign(n + 1, 0);
    for (int i = 1; i <= n; i++)
    {
        for (auto [v, w] : g[i])
        {
            du[v]++;
        }
    }
    vector<int> p(q + 1);
    for (int i = 1; i <= q; i++)
    {
        cin >> p[i];
    }
    vector<ll> f(n + 1, 0), dp(n + 1, inf);
    vector<multiset<ll>> st(n + 1);
    queue<int> t;
    for (int i = 1; i <= n; i++)
    {
        if (!du[i])
        {
            t.push(i);
        }
    }
    while (t.size())
    {
        int u = t.front();
        t.pop();
        for (auto [v, w] : g[u])
        {
            du[v]--;
            dp[v] = min(dp[v], w);
            st[v].insert(w);
            if (!du[v])
            {
                t.push(v);
            }
        }
    }
    ll ans = 0;
    for (int i = q; i >= 1; i--)
    {
        int now = p[i];
        if (i + 1 <= q && p[i] == p[i + 1])
            continue;
        ll pre = f[now];
        f[now] = dp[now];

        for (auto [v, w] : g[now])
        {
            f[now] = min(f[now], w + f[v]);
        }
        for (auto [v, w] : g[now])
        {
            st[v].extract(pre + w);
            st[v].insert(f[now] + w);
            dp[v] = *st[v].begin();
        }
    }
    for (int i = 1; i <= n; i++)
    {
        ans += 1ll * a[i] * f[i] % mod;
        ans %= mod;
    }

    cout << ans << '\n';
}
int main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int _ = 1;
    // cin >> _;
    while (_--)
        solve();
    return 0;
}