#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <deque>
#include <queue>
#include <array>
#include <set>
#include <map>
#include <cmath>
#include <complex>
#include <algorithm>
#include <numeric>
#include <utility>
#include <tuple>
#include <bitset>
#include <cstdint>
#include <cassert>
#include <random>
#include <iterator>

using namespace std;
using i64 = int64_t;
using i32 = int32_t;

int main() {
    i64 n, m, k;
    char op;
    cin >> n >> m >> k >> op;
    vector<i64> a(n), b(m);
    for (int i = 0; i < m; ++i) cin >> b[i];
    for (int i = 0; i < n; ++i) cin >> a[i];
    sort(begin(b), end(b));

    i64 ans = 0;
    for (int i = 0; i < n; ++i) {
        i64 x = op == '+' ? k - a[i] : (k + a[i] - 1) / a[i];
        auto it = lower_bound(begin(b), end(b), x);
        ans += end(b) - it;
    }
    cout << ans << endl;
    return 0;
}