#include<bits/stdc++.h>
using namespace std;

typedef long long ll;

int main(){
        ll n,m,k,tmp=0;
        cin>>n>>m>>k;
        ll sum1=0,sum2=0;
        vector<ll>a(n),b(m);
        char op;
        bool add=false;
        cin>>op;
        if(op=='+')add=true;
        for(int i=0;i<m;i++){
                cin>>b[i];
        }
        sort(b.begin(),b.end());
        for(int i=0;i<n;i++){
                cin>>a[i];
        }
        sort(a.begin(),a.end());
        for(int i=0;i<n;i++){
                if(add){
                                tmp+=b.end()-lower_bound(b.begin(),b.end(),k-a[i]);
                }else{
                                tmp+=b.end()-lower_bound(b.begin(),b.end(),(k+a[i]-1)/a[i]);
                }
        }
        cout<<tmp<<endl;
        return 0;
}