#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, m, k;
    cin >> n >> m >> k;

    char op;
    cin >> op;

    vector<int> b(m);
    for (int j = 0; j < m; j++) {
        cin >> b[j];
    }
    sort(b.begin(), b.end(), greater<>());

    vector<int> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    sort(a.begin(), a.end());

    ll r = 0;
    int j = 0;
    for (int i = 0; i < n; i++) {
        while (j < m) {
            ll t = op == '+' ? a[i] + b[j] : (ll)a[i] * b[j];
            if (t < k) break;
            j++;
        }
        r += j;
    }

    cout << r << endl;

    return 0;
}