#include <cstdio>
#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>
#include <numeric>
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

const long long MAX = 5100000;
const long long INF = 1LL << 60;
//const long long mod = 1000000007LL;
//const long long mod = 998244353LL;

using namespace std;
typedef unsigned long long ull;
typedef long long ll;


ll A[150000];
ll B[150000];
int main()
{
	/*
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	*/
	ll N, M, K; scanf("%lld %lld %lld", &N, &M, &K);
	char c; cin >> c;
	for (ll i = 0; i < M; i++) scanf("%lld", &B[i]);
	for (ll i = 0; i < N; i++) scanf("%lld", &A[i]);
	sort(B, B + M);
	sort(A, A + N);
	ll res = 0;
	if (c == '+') {
		for (ll i = 0; i < N; i++) {
			res += M - (lower_bound(B, B + M, K - A[i]) - B);
		}
	}
	else {
		for (ll i = 0; i < N; i++) res += M - (lower_bound(B, B + M, (K + A[i] - 1) / A[i]) - B);

	}
	cout << res << endl;
	return 0;
}