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

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int N,M; ll K; cin >> N >> M >> K;
    char op; cin >> op;
    vector<ll> A(N),B(M);
    for (int i=0;i<M;++i) cin >> B[i];
    for (int i=0;i<N;++i) cin >> A[i];
    sort(B.begin(),B.end());
    reverse(B.begin(),B.end());
    sort(A.begin(),A.end());
    ll ans=0,now=0;
    for (int i=0;i<N;++i){
        if (op=='+') while(now<M&&A[i]+B[now]>=K) ++now;
        else while(now<M&&A[i]*B[now]>=K) ++now;
        ans+=now;
    }
    cout << ans << '\n';
}