#include "bits/stdc++.h"
using namespace std;
#define int long long
#define REP(i,n) for(int i = 0;i < (int)(n);i++)
#define RREP(i,n) for(int i = (int)n-1;i >= 0;i--)
#define FOR(i,s,n) for(int i = s;i < (int)n;i++)
#define RFOR(i,s,n) for(int i = (int)n-1;i >= s;i--)
#define ALL(a) a.begin(),a.end()
#define IN(a, x, b) (a<=x && x<b)
template<class T>inline void out(T t){cout<<t<<"\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout<<t<<" ";out(ts...);}
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;}
constexpr long long INF = 1e18;

signed main(){
	int N,M,K;
	cin >> N >> M >> K;
	char c;
	cin >> c;
	vector<int>a(N),b(M);
	REP(i,M)cin >> b[i];
	REP(i,N)cin >> a[i];
	sort(ALL(a));
	sort(ALL(b));
	int ans = 0;
	if(c == '+'){
		REP(i,N){
			auto itr = lower_bound(ALL(b),K-a[i])-b.begin();
			ans += M - itr;
		}
	}else{
		REP(i,N){
			int target = (K + a[i] - 1) / a[i];
			auto itr = lower_bound(ALL(b),target)-b.begin();
			ans += M - itr;
		}
	}
	out(ans);
}