#include<iostream>
#include<algorithm>
using namespace std;
int N,M;
char op;
long A[1<<17],B[1<<17];
long K,ans;
main()
{
	cin>>N>>M>>K;
	cin>>op;
	for(int j=0;j<M;j++)
	{
		cin>>B[j];
	}
	sort(B,B+M);
	for(int i=0;i<N;i++)
	{
		cin>>A[i];
		ans+=B+M-lower_bound(B,B+M,op=='+'?K-A[i]:(K+A[i]-1)/A[i]);
	}
	cout<<ans<<endl;
}