#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(0), cin.tie(0)
#define int long long
#define ll long long
#define int128 __int128
#define ull unsigned long long
#define endl "\n"
#define pi acos(-1)
#define pii pair<int, int>
const double eps = 1e-6;
const int N = 1e6 + 10, M = 1010, INF = 0x3f3f3f3f;
const int mod = 998244353;
int a[N];
vector<pii> s[N];
bool cmd(pii x, pii y)
{
    return x.second < y.second;
}
void solve()
{
    int n, m, q;
    cin >> n >> m >> q;
    for (int i = 1; i <= n; i++)
        cin >> a[i];
    for (int i = 0; i < m; i++)
    {
        int x, y, z;
        cin >> x >> y >> z;
        s[x].push_back({y, z});
        s[y].push_back({x, z});
    }
    for (int i = 1; i <= n; i++)
        sort(s[i].begin(), s[i].end(), cmd);
    int ans = 0;
    while (q--)
    {
        int x;
        cin >> x;
        if (a[x])
        {
            ans = (ans + a[x] * s[x][0].second % mod) % mod;
            a[s[x][0].first] += a[x];
            a[x] = 0;
        }
    }
    cout << ans << endl;
}
signed main()
{
    ios;
    int T = 1;
    // cin >> T;
    // cout << fixed << setprecision(8);
    for (int i = 1; i <= T; i++)
    {
        // cout << "Case " << i << ": ";
        solve();
    }

    return 0;
}