#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int (i)=0;(i)<(n);(i)++)
int main() {
  int n, m, k;
  cin >> n >> m >> k;
  char op;
  cin >> op;
  vector<long long> b(m);
  vector<long long> a(n);
  rep(i, m) cin >> b[i];
  rep(i, n) cin >> a[i];
  sort(a.begin(), a.end());
  sort(b.begin(), b.end());
  if(op == '+') {
    long long total = 0;
    rep(i, n) {
      int c = k - a[i];
      auto it = lower_bound(b.begin(), b.end(), c);
      int dist = distance(b.begin(), it);
      total += m - dist;
    }
    cout << total << endl;
  }
  else {
    long long total = 0;
    rep(i, n) {
      int c;
      if(k % a[i] == 0) c = k / a[i];
      else c = (k / a[i] + 1);
      auto it = lower_bound(b.begin(), b.end(), c);
      int dist = distance(b.begin(), it);
      total += m - dist;
    }
    cout << total << endl;
  }
}