#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i = 0; i < (int)(n); ++i)
#define all(x) x.begin(),x.end()
#define ln '\n'
const long double PI = acos(-1.0L);
const long long MOD = 1000000007LL;
// const long long MOD = 998244353LL;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
template<class T> inline bool chmax(T &a, T b) { if (a < b) { a = b; return true;} return false; }
template<class T> inline bool chmin(T &a, T b) { if (a > b) { a = b; return true;} return false; }
////////////////////////////////////////////////////////////////////////////////////////////////////////////

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    ll N,M,K; cin >> N >> M >> K;
    char c; cin >> c;
    vector<ll> B(M),A(N);
    rep(i,M) cin >> B[i];
    rep(i,N) cin >> A[i];
    
    sort(all(A)); sort(all(B));
    if (c == '+') {
        ll ans = 0;
        rep(i,N) {
            ll k = B.end() - lower_bound(all(B),K-A[i]);
            ans += k;
        }
        cout << ans << ln;
    } else {
        ll ans = 0;
        rep(i,N) {
            ll k = B.end() - lower_bound(all(B),(K+A[i]-1)/A[i]);
            ans += k;
        }
        cout << ans << ln;
    }
}