#include <iostream>
using namespace std;

struct iostream_init_struct
{ 
	iostream_init_struct()
	{
		std::cin.tie(0);
		std::cin.sync_with_stdio(false);
	}
} iostream_init;

#include <string>
#include <vector>
#include <algorithm>
int N;
string s[100000];
int M, x, d, i, j;

void next()
{
	i = (x / (N - 1));
	j = (x % (N - 1));
	if (i > j)
	{
		int temp = i;
		i = j;
		j = temp;
	}
	else
	{
		j = j + 1;
	}
	x = (x + d) % (N * (N - 1));
}

int LCP()
{
	int ret = 0;
	while (ret < min(s[i].size(), s[j].size()))
	{
		if (s[i][ret] == s[j][ret])
		{
			++ret;
		}
		else
		{
			break;
		}
	}

	return ret;
}

int main()
{
	cin >> N;
	for (int i = 0; i < N; ++i)
	{
		cin >> s[i];
	}
	cin >> M >> x >> d;

	int sum = 0;
	for (int indx = 0; indx < M; ++indx)
	{
		next();
		sum += LCP();
	}

	cout << sum << endl;
}