# coding: utf-8
import array, bisect, collections, copy, heapq, itertools, math, random, re, string, sys, time
sys.setrecursionlimit(10 ** 7)
INF = 10 ** 20
MOD = 10 ** 9 + 7


def II(): return int(input())
def ILI(): return list(map(int, input().split()))
def IAI(LINE): return [ILI() for __ in range(LINE)]
def IDI(): return {key: value for key, value in ILI()}


def makeQuery(N, M, x, d):
    query = []
    i = list(range(1, N + 1))
    j = list(range(1, N + 1))
    for k in range(1, M + 1):
        i[k] = (x // (N - 1)) + 1
        j[k] = (x % (N - 1)) + 1
        if i[k] > j[k]:
            i[k], j[k] = j[k], i[k]
        else:
            j[k] = j[k] + 1
        x = (x + d) % (N * (N - 1))
    for q in range(1, N):
        query.append((i[q], j[q]))

    return query


def solve(N, s, M, x, d):
    query = makeQuery(N, M, x, d)
    ans = 0
    for q in query:
        s_i = s[q[0] - 1]
        s_j = s[q[1] - 1]
        n_len = min(len(s_i), len(s_j))
        l_lcp = []
        n_lcp = 0
        for i in range(n_len):
            if s_i[i] == s_j[i]:
                n_lcp += 1
            else:
                l_lcp.append(n_lcp)
                break
        else:
            l_lcp.append(n_lcp)
        ans += max(l_lcp)

    return ans


def main():
    N = II()
    s = [input() for __ in range(N)]
    M, x, d = ILI()
    print(solve(N, s, M, x, d))


if __name__ == "__main__":
    main()