#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  int n, m, k;
  cin >> n >> m >> k;
  char op;
  cin >> op;

  vector<int> A(n), B(m);

  REP (i, m) cin >> B[i];
  REP (i, n) cin >> A[i];
  sort(B.begin(), B.end());
  
  long long ret = 0;

  if (op == '+') {
    REP (i, n) {
      int j = lower_bound(B.begin(), B.end(), k - A[i]) - B.begin();
      ret += m - j;
    }
  } else {
    REP (i, n) {
      int j = lower_bound(B.begin(), B.end(), (k + A[i] - 1)/ A[i]) - B.begin();
      ret += m - j;
    }
  }

  cout << ret << endl;
  
  return 0;
}