#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i,n) for(int i=0; i<(n); i++)
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
int main(){
    ll n,m,k; cin>>n>>m>>k;
    char op; cin>>op;
    vector<ll> a(n), b(m);
    rep(i,m) cin>>b[i];
    rep(i,n) cin>>a[i];
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());
    if(op=='+'){
        ll res=0;
        rep(i,n){
            auto Iter=lower_bound(b.begin(), b.end(), k-a[i]);
            res+=b.end()-Iter;
        }
        cout<<res<<endl;
    }else{
        ll res=0;
        rep(i,n){
            ll key=0;
            if(k%a[i]==0) key=k/a[i];
            else key=k/a[i]+1;
            auto Iter=lower_bound(b.begin(), b.end(), key);
            res+=b.end()-Iter;
        }
        cout<<res<<endl;
    }
    return 0;
}