#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

int pref[100001], pref2[100001];
vector<int> c(100000);
vector<pair<int, int> > shops(100000);
vector<int> farms(100000);

bool comp(pair<int, int> p, pair<int, int> q) {
    return p.second > q.second;
}

int rent(int i) {
    return pref[i];
}

void setIO(string s) {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

int produce(int cow) {
    vector<pair<int, int> > shops2(100000);
    for(int i = 0; i < 100000; ++i) {
        shops2[i] = shops[i];
    }
    int prefsum = pref2[cow];
    int mon = 0;
    int shop_ind = 0;
    //for (int cow = 0; cow < 100000; cow++) {
    while (shops2[shop_ind].first > 0) {
        int sell = min(prefsum, shops2[shop_ind].first);
        prefsum -= sell;
        shops2[shop_ind].first -= sell;
        mon += sell * shops2[shop_ind].second;
        if (shops2[shop_ind].first == 0) {
            shop_ind++;
        }
        if (prefsum == 0) {
            break;
        }
    }
    //}
    return mon;
}
int main() {
    setIO("rental");
    int N, M, R;
    cin >> N >> M >> R; //cows, stores, neighbors
    for (int i = 0; i < N; i++) {
        cin >> c[i];
    }
    sort(c.rbegin(), c.rend());
    for(int i = 1; i <= N; ++i) {
        pref2[i] = pref2[i - 1] + c[i - 1];
    }
    for (int i = 0; i < M; i++) {
        cin >> shops[i].first >> shops[i].second;
    }
    sort(shops.begin(), shops.end(), comp);
    for (int i = 0; i < R; i++) {
        cin >> farms[i];
    }
    sort(farms.rbegin(), farms.rend());
    for(int i = 1; i <= R; ++i) {
        pref[i] = pref[i - 1] + farms[i - 1];
    }
    int ans = 0;
    for (int i = 0; i <= min(N, R); i++) {
        ans = max(produce(N - i) + rent(i), ans);
    }
    cout << ans << endl;
}