#pragma GCC optimize("O3")
#include<bits/stdc++.h> 
using namespace std;
using ll=long long;
typedef  unsigned long long int ull;
//typedef pair<ll,ll> P;
template<class T> using V=vector<T>; 
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
const ll inf=(1e18);
//const ll mod=998244353;
const ll mod=1000000007;
ll gcd(ll a,ll b) {return b ? gcd(b,a%b):a;}
ll lcm(ll c,ll d){return c/gcd(c,d)*d;}
struct __INIT{__INIT(){cin.tie(0);ios::sync_with_stdio(false);cout<<fixed<<setprecision(15);}} __init;
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }
int main(){
    ll n,m,k;
    cin>>n>>m>>k;
    char c;
    cin>>c;
    V<ll> b(m);
    for(int i=0;i<m;i++)cin>>b[i];
    V<ll> a(n);
    for(int i=0;i<n;i++)cin>>a[i];
    sort(all(a));
    ll ans=0;
    for(int i=0;i<m;i++){
        if(c=='*')ans+=a.end()-lower_bound(all(a),(k+b[i]-1)/b[i]);
        else ans+=a.end()-lower_bound(all(a),k-b[i]);
    }
    cout<<ans<<"\n";
}