#include <string>
#include <vector>
#include <iostream>
#include <algorithm>
#include <functional>
using namespace std;
int main() {
	int N, M, K; string op;
	cin >> N >> M >> K >> op;
	vector<int> B(M), A(N);
	for (int i = 0; i < M; ++i) cin >> B[i];
	for (int i = 0; i < N; ++i) cin >> A[i];
	sort(A.begin(), A.end());
	sort(B.begin(), B.end());
	long long ans = 0;
	for (int i = 0; i < N; ++i) {
		int least = (op == "+" ? K - A[i] : (K + A[i] - 1) / A[i]);
		ans += B.end() - lower_bound(B.begin(), B.end(), least);
	}
	cout << ans << endl;
	return 0;
}