#include <iostream>
#include <iomanip>
#include <vector>
#include <utility>
#include <map>
#include <algorithm>
#include <queue>
#include <cmath>
#include <numeric>
#include <set>

using namespace std;
struct aaa{aaa(){cin.tie(nullptr); ios::sync_with_stdio(false); cout<<fixed<<setprecision(20);};}aaa;
template <class T>ostream &operator<<(ostream &o,const vector<T>&v){o<<"{";for(int i=0;i<(int)v.size();i++)o<<(i>0?", ":"")<<v[i];o<<"}";return o;}
#define debug(v) {cerr<<"\033[1;36m[debug]\033[m "<<#v<<" : "<<v<<endl;}

using int64 = long long;

int main() {
    int64 n,m,k;
    int64 ans = 0;
    cin >> n >> m >> k;
    char op; cin >> op; bool plus = op == '+';
    vector<int64> b(m);
    vector<int64> a(n);
    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());

    for (int i=0; i<n; i++) {
        int m = (plus? k-a[i] : (k+a[i]-1)/a[i]);
        auto it = lower_bound(b.begin(), b.end(), m);
        ans += (b.end() - it);
    }

    cout << ans << endl;
}