import sys

def solve():
  def ilog2(n):
    return 0 if n <= 0 else n.bit_length() - 1

  input = sys.stdin.readline

  N = int(input())
  strs = [input().rstrip() for _ in range(N)]
  M, x, d = map(int, input().split())

  perm = [i for i in range(N)]
  perm.sort(key=lambda i: strs[i])
  iperm = [0] * N
  for i, p in enumerate(perm):
    iperm[p] = i

  size = N - 1
  lcp = [0] * size
  for i in range(size):
    s1, s2 = strs[perm[i]], strs[perm[i + 1]]
    lcp[i] = l = min(len(s1), len(s2))
    for j in range(l):
      if s1[j] != s2[j]:
        lcp[i] = j
        break

  lgN = ilog2(size)
  tab = [lcp]
  for k in range(1, lgN + 1):
    s = 1 << (k - 1)
    prev, curr = tab[-1], [0] * (size + 1 - 2 * s)
    for i in range(len(curr)):
      curr[i] = min(prev[i], prev[i + s])
    tab += [curr]

  ans = 0
  mod = N * (N - 1)
  for _ in range(M):
    i, j = divmod(x, N - 1)
    j += (i <= j)
    i, j = iperm[i], iperm[j]
    if i > j:
      i, j = j, i
    l = ilog2(j - i)
    ans += min(tab[l][i], tab[l][j - (1 << l)])
    x += d
    if x >= mod:
      x -= mod

  print(ans)

solve()