#include <bits/stdc++.h>
using namespace std;

int main() {
	int64_t n, m, k; cin >> n >> m >> k;
	char op; cin >> op;
	vector<int64_t> b(m); for(int i = 0; i < m; ++i) cin >> b[i];
	vector<int64_t> a(n); for(int i = 0; i < n; ++i) cin >> a[i];
	sort(b.begin(), b.end());
	int64_t ans = 0;
	if(op == '+') {
		for(int i = 0; i < n; ++i) {
			ans += b.end() - lower_bound(b.begin(), b.end(), k - a[i]);
		}
	} else {
		for(int i = 0; i < n; ++i) {
			ans += b.end() - lower_bound(b.begin(), b.end(), (k + a[i] - 1) / a[i]);
		}
	}
	cout << ans << '\n';
	return 0;
}