#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<bitset>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<deque>
#include<list>
#include<iomanip>
#include<cmath>
#include<cstring>
#include<functional>
using namespace std;

#define repr(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define rep(i, n) repr(i, 0, n)
#define INF 2e9
#define MOD 1000000007
//#define MOD 998244353
#define LINF (long long)4e18
#define jck 3.141592

using ll = long long;
using Pi = pair<int,int>;
using Pl = pair<ll,ll>;


int main(){
    int N,M,K; cin >> N >> M >> K;
    char op; cin >> op;
    vector<ll> A(N),B(M);
    rep(i,M) cin >> B[i];
    rep(i,N) cin >> A[i];
    sort(A.begin(),A.end());
    sort(B.begin(),B.end());
    if(op == '+'){
        ll ans = 0;
        rep(i,N){
            ans += B.end()-lower_bound(B.begin(),B.end(),K-A[i]);
        }
        cout << ans << endl;
    }
    else{
        ll ans = 0;
        rep(i,N){
            ans += B.end()-lower_bound(B.begin(),B.end(),(K+A[i]-1)/A[i]);
        }
        cout << ans << endl;
    }

}