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

int main() {
  long N, M, K;
  char op;
  cin >> N >> M >> K >> op;
  vector<long> A(N), B(M);
  for (auto &b : B) cin >> b;
  sort(B.begin(), B.end());
  for (auto &a : A) cin >> a;
  sort(A.begin(), A.end());

  long ans = N * M;
  if (op == '+') {
    for (int i = 0; i < N; i++)
      if (A.at(i) < K) ans -= lower_bound(B.begin(), B.end(), K - A.at(i)) - B.begin();
  } else {
    for (int i = 0; i < N; i++)
      if (A.at(i) < K) ans -= lower_bound(B.begin(), B.end(), (K + A.at(i) - 1) / A.at(i)) - B.begin();
  }
  cout << ans << "\n";
}