N = int(input())
S = list(str(input()))
MOD = 10**9+7
alp = list(' yukicoder')
M = len(alp)
dp = [[[0,0] for _ in range(11)] for _ in range(N+1)]
dp[0][0][0] = 1

for i in range(1,N+1):
  s = S[i-1]
  for j in range(M):
    dp[i][j][0] = dp[i-1][j][0]
    dp[i][j][1] = dp[i-1][j][1]
  if s != '?':
    for k in range(M):
      if s == alp[k]:
        j = k
        break
    dp[i][j][0] += dp[i-1][j-1][0]
    dp[i][j][0] %= MOD
    dp[i][j][1] += dp[i-1][j-1][1]
    dp[i][j][1] %= MOD
  else:
    for k in range(1,M):
      dp[i][k][1] += dp[i-1][k-1][0]
      dp[i][k][1] %= MOD

print(dp[N][M-1][0]+dp[N][M-1][1])