#include <iostream>
#include <algorithm>
using namespace std;
typedef long long ll;

int main() {
  ll n,m,k; cin>>n>>m>>k;
  char ch; cin>>ch;
  ll b[m], a[n], ans=0;
  for(int i=0;i<m;i++) cin>>b[i];
  for(int i=0;i<n;i++) cin>>a[i];

  sort(a,a+n); sort(b,b+m);

  if (ch=='+') {
    for(int i=0;i<m;i++) {
      //cout<<distance(lower_bound(a, a+n, k-b[i]), a+n)<<" ";
      ans += distance(lower_bound(a, a+n, k-b[i]), a+n);
    }
  } else {
    for(int i=0;i<m;i++) {
      //cout<<distance(lower_bound(a, a+n, (k/b[i])+(k%b[i]>0)), a+n)<<" ";
      ans += distance(lower_bound(a, a+n, (k/b[i])+(k%b[i]>0)), a+n);
    }
  }
  cout<<ans<<endl;
}