#pragma GCC optimize("O3")
#pragma GCC target("avx")
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

#define INF (1<<29)
class RMQ{
	int size;
	vector<int> minval;
	vector<int> maxval;
	pair<int,int> _query(int a,int b,int k,int l, int r){
		if(r<=a||b<=l)return make_pair(INF,-INF);
		if(a<=l&&r<=b)return make_pair(minval[k],maxval[k]);
		else{
			pair<int,int> vl=_query(a,b,k*2+1,l,(l+r)/2);
			pair<int,int> vr=_query(a,b,k*2+2,(l+r)/2,r);
			return make_pair(min(vl.first,vr.first),max(vl.second,vr.second));
		}
	}

public:
	RMQ(int k){init(k);}
	void init(int k){
		for(size=1;size<k;)size<<=1;
		//size=1<<(32-__builtin_clz(k));
		minval=vector<int>(2*size-1,INF);
		maxval=vector<int>(2*size-1,-INF);
	}

	void update(int k,int t){
		k+=size-1;
		minval[k]=maxval[k]=t;
		while(k>0){
			k=(k-1)/2;
			minval[k]=min(minval[k*2+1],minval[k*2+2]);
			maxval[k]=max(maxval[k*2+1],maxval[k*2+2]);
		}
	}

	pair<int,int> query(int a,int b){
		return _query(a,b,0,0,size);
	}
};

int N,D,I,J;
long long X;
void iterate(){
	I=X/~-N;
	J=X%~-N;
	if(I>J)swap(I,J);
	else J++;
	X=(X+D)%((long long)N*~-N);
}
int calc(const string &s,const string &t){
	int l=min(s.size(),t.size()),i=0;
	for(;i<l&&s[i]==t[i];i++);
	return i;
}
int main(){
	int M,R=0;
	cin>>N;
	vector<pair<string,int>>v(N);
	vector<int>rev(N);
	for(int i=0;i<N;i++)cin>>v[i].first,v[i].second=i;
	cin>>M>>X>>D;
	sort(v.begin(),v.end());
	for(int i=0;i<N;i++)rev[v[i].second]=i;
	RMQ rmq(N-1);
	for(int i=0;i<N-1;i++)rmq.update(i,calc(v[i].first,v[i+1].first));
	for(;M--;){
		iterate();
		R+=rmq.query(rev[I],rev[J]).first;
	}
	cout<<R<<endl;
}