#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i,m,n) for(int i=m; i<n; ++i)
#define repl(i,m,n) for(ll i=m; i<n; ++i)

int main(){
    ll N, M, K; char op;
    cin >> N >> M >> K >> op;
    vector<ll> A(N), B(M);
    rep(i, 0, M) cin >> B[i];
    rep(i, 0, N) cin >> A[i];

    sort(B.begin(), B.end());

    ll ans = 0LL;
    repl(i, 0, N){
        if(A[i] >= K){
            ans += M; 
            continue;
        }
        ll key;
        if(op == '+'){
            key = K - A[i];
        }else{
            key = (K + A[i] - 1LL) / A[i];
        }
        auto it = lower_bound(B.begin(), B.end(), key);
        ans += ll(M - (it - B.begin()));
    }
    cout << ans << endl;

    return 0;
}