#ifdef _DEBUG
#define _GLIBCXX_DEBUG
#endif
#define _CRT_SECURE_NO_WARNINGS
#include <ext/pb_ds/assoc_container.hpp>
#include <bits/stdc++.h>

using namespace __gnu_pbds;
using namespace std;

typedef long long ll;
typedef vector<ll> vll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef long double ld;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

#define mk make_pair
#define inb push_back
#define enb emplace_back
#define X first
#define Y second
#define all(v) v.begin(), v.end()
#define sqr(x) (x) * (x)
#define TIME 1.0 * clock() / CLOCKS_PER_SEC
#define y1 AYDARBOG
//continue break pop_back return

int solve();

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
#define TASK "robots"
#ifndef _DEBUG
    //freopen(TASK".in", "r", stdin), freopen(TASK".out", "w", stdout);
#endif
    solve();
//#ifdef _DEBUG
    fprintf(stderr, "\nTIME: %.3f\n", TIME);
//#endif
}

const ll INF = 2e18 + 7;

const int BUFSZ = (int)4e6 + 7;
char buf[BUFSZ];
string get_str()
{
    scanf(" %s", buf);
    return string(buf);
}

int solve()
{
    int n, m, k;
    cin >> n >> m >> k;
    vector<vector<pii>> g(n);
    vector<pair<int, pii>> e;
    for (int i = 0; i < m; ++i)
    {
        int x, y, c;
        cin >> x >> y >> c;
        --x, --y;
        e.inb(mk(c, mk(x, y)));
        g[x].inb(mk(y, c));
        g[y].inb(mk(x, c));
    }
    sort(all(e));
    vector<pii> ee(k);
    for (int i = 0; i < k; ++i)
    {
        cin >> ee[i].X >> ee[i].Y;
        --ee[i].X, --ee[i].Y;
    }
    vi cnt(n);
    ll sumcnt = 0;
    for (int i = 0; i < n; ++i)
    {
        cin >> cnt[i];
        sumcnt += cnt[i];
    }
    //printf("SUMCNT : %lld\n", sumcnt);
    vi p(n), r(n);
    ll ans = 0;
    for (int msk = 0; msk < (1 << k); ++msk)
    {
        if (msk == 0)
            continue;
        int sz = __builtin_popcount(msk);
        vector<pii> ce;
        for (int i = 0; i < k; ++i)
        {
            if ((msk >> i) & 1)
            {
                ce.inb(ee[i]);
            }
        }
        for (int I = 0; I < sz; ++I)
        {
            g.clear();
            g.resize(n);
            for (int i = 0; i < n; ++i)
            {
                p[i] = i;
                r[i] = 0;
            }
            function<int(int)> get = [&](int u)
            {
                if (p[u] == u)
                    return u;
                return p[u] = get(p[u]);
            };
            vector<pair<int, pii>> eo;
            for (int i = 0; i < sz; ++i)
            {
                if (i != I)
                {
                    int x = get(ce[i].X);
                    int y = get(ce[i].Y);
                    if (x != y)
                    {
                        if (r[x] < r[y])
                            swap(r[x], r[y]);
                        p[y] = x;
                        if (r[x] == r[y])
                            ++r[x];
                        g[ce[i].X].inb(mk(ce[i].Y, 0));
                        g[ce[i].Y].inb(mk(ce[i].X, 0));
                        eo.inb(mk(0, ce[i]));
                    }
                }
            }
            for (int i = 0; i < m; ++i)
            {
                int x = get(e[i].Y.X);
                int y = get(e[i].Y.Y);
                if (x != y)
                {
                    if (r[x] < r[y])
                        swap(r[x], r[y]);
                    p[y] = x;
                    if (r[x] == r[y])
                        ++r[x];
                    g[e[i].Y.X].inb(mk(e[i].Y.Y, e[i].X));
                    g[e[i].Y.Y].inb(mk(e[i].Y.X, e[i].X));
                    //printf("COST :: %d  BTW :: %d %d\n", e[i].X, e[i].Y.X + 1, e[i].Y.Y + 1);
                    eo.inb(e[i]);
                }
            }
            //printf("%d\n", (int)eo.size());
            //postroili s pacanami ostov
            pii cure = ce[I];
            vi rx(n), ry(n);
            function<void(int, int, vi&)> dfsr = [&](int u, int pr, vi &rr)
            {
                for (pii tt : g[u])
                {
                    int to = tt.X;
                    if (to == pr)
                        continue;
                    rr[to] = rr[u] + 1;
                    dfsr(to, u, rr);
                }
            };
            dfsr(ce[I].X, -1, rx);
            dfsr(ce[I].Y, -1, ry);
            int mxcst = 0;
            for (int i = 0; i < (int)eo.size(); ++i)
            {
                int cdstx = rx[eo[i].Y.X] + ry[eo[i].Y.X];
                int cdsty = rx[eo[i].Y.Y] + ry[eo[i].Y.Y];
                //printf("COST :: %d CDST :: %d\n", eo[i].X, cdst);
                if (rx[cure.Y] == cdstx && cdstx == cdsty)
                {
                    mxcst = max(mxcst, eo[i].X);
                }
            }
            if (mxcst == 0)
                continue;
            ll curcnt = 0;
            function<void(int, int)> dfscnt = [&](int u, int pr)
            {
                curcnt += cnt[u];
                for (pii tt : g[u])
                {
                    int to = tt.X;
                    int cc = tt.Y;
                    if (to == pr || cc == mxcst)
                        continue;
                    dfscnt(to, u);
                }
            };
            dfscnt(0, 0);
            ans = max(ans, 1ll * (sumcnt - curcnt) * mxcst);
        }
    }
    printf("%lld\n", ans);
    return 0;
}