from copy import deepcopy

N = int(input())
S = input()
MOD = 10 ** 9 + 7
L = 9

dp0 = [0] * (L + 1)  # ? が入らない
dp0[0] = 1
dp1 = [[0] * (L + 1) for _ in range(L)]  # ? が入る
for i in range(L):
    dp1[i][0] = 1

d = {s: i for i, s in enumerate('yukicoder')}
d['?'] = -1

for s in S:
    new_dp0 = dp0.copy()
    new_dp1 = deepcopy(dp1)
    if s not in d:
        continue
    si = d[s]
    if si == -1:
        for i in range(L):
            new_dp1[i][i + 1] += dp1[i][i]
            new_dp1[i][i + 1] %= MOD
    else:
        new_dp0[si + 1] += dp0[si]
        new_dp0[si + 1] %= MOD
        for i in range(L):
            if i != si:
                new_dp1[i][si + 1] += dp1[i][si]
                new_dp1[i][si + 1] %= MOD
    dp0 = new_dp0
    dp1 = new_dp1
ans = (dp0[-1] + sum(dp1[i][-1] for i in range(9))) % MOD
print(ans)