#include <cstdio>
#include <queue>
#define mp make_pair

using namespace std;

//priority_queue <pair <int, pair <int, int> >, vector <pair <int, pair <int, int> > >, greater <pair <int, pair <int, int> > > > Ha, Hb;

const int N = 50005;

bool used[2 * N];

int n, na, nb, ta[N], tb[N], timp[2 * N];

void read() {
    freopen("fabrica.in", "r", stdin);
    freopen("fabrica.out", "w", stdout);

    scanf("%d%d%d", &n, &na, &nb);

    for (int i = 1; i <= na; ++ i)
        scanf("%d", &ta[i]);

    for (int i = 1; i <= nb; ++ i)
        scanf("%d", &tb[i]);
}

int max(int x, int y) {
    return x > y ? x : y;
}

priority_queue <pair <int, int>, vector <pair <int, int> >, greater <pair <int, int> > > Ha;

void solve_a() {
    pair<int, int> tpa;
    int tma = - 1;

    for (int i = 1; i <= na; ++ i)
        Ha.push(mp(ta[i], ta[i]));

    for (int i = 1; i <= n; ++ i) {
        tpa = Ha.top();
        Ha.pop();
        timp[i] = tpa.first;
        Ha.push(mp(tpa.first + tpa.second, tpa.second));
        if (timp[i] > tma)
            tma = timp[i];
    }

    printf("%d", tma);
}

int main() {
    read();
    solve_a();
    return 0;
}