#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++)
#define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++)
#define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--)
#define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())
#define len(x) ((ll)(x).length())

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    ll n, m, k;
    cin >> n >> m >> k;
    char op;
    cin >> op;
    vector<ll> b(m), a(n);
    rep(i, m) cin >> b[i];
    rep(i, n) cin >> a[i];
    sort(all(b));
    sort(all(a));
    ll ans = 0;
    rep(i, n) {
        ll v = 0;
        if (op == '+') v = k - a[i];
        else v = (k + (a[i] - 1)) / a[i];
        ll cnt = m - (lower_bound(all(b), v) - b.begin());
        ans += cnt;
    }
    cout << ans << endl;
    return 0;
}