#include<iostream>
#include<string>
#include<iomanip>
#include<cmath>
#include<vector>
#include<algorithm>

using namespace std;

#define int long long
#define endl "\n"

constexpr long long INF = (long long)1e18;
constexpr long long MOD = 1'000'000'007; 

string yn(bool f){return f?"Yes":"No";}
string YN(bool f){return f?"YES":"NO";}



signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	cout<<fixed<<setprecision(10);
	
	int N, M, K;
	vector<int> A, B, a, b;
	string op;
	int con = 0;
	cin>>N>>M>>K;
	
	cin>>op;
	
	B.resize(M);
	A.resize(N);
	
	
	for(int i = 0; i < M; i++){
		cin>>B[i];
	}
	for(int i = 0; i < N; i++){
		cin>>A[i];
	}
	
	a = A;
	b = B;
	
	sort(a.begin(), a.end());
	if(op == "+") {
		for(int i = 0; i < M; i++){
			int x = K - B[i];
			con += N - (lower_bound(a.begin(), a.end(), x) - a.begin());
			// cout<<x<<" "<<con<<endl;
		}
	} else {
		for(int i = 0; i < M; i++){
			int x = (K + B[i] - 1)/B[i];
			con += N - (lower_bound(a.begin(), a.end(), x) - a.begin());
		}
	}
	
	cout<<con<<endl;
	
	return 0;
}