from itertools import pairwise


def accum_dp(xs: list, f, op, e, init: dict):
    dp = init.copy()
    for x in xs:
        pp = {}
        dp, pp = pp, dp
        for fm_key, fm_val in pp.items():
            for to_key, to_val in f(fm_key, fm_val, x):
                dp[to_key] = op(dp.get(to_key, e), to_val)

    return dp


def op(a, b):
    return (a + b) % MOD


def solve(pat: str):
    def f(k, v, x):
        yield k, v  # 採用しない

        # 採用する
        for (a, b) in pairs:
            if (k, x) == (a, b):
                yield x, v

    pairs = list(pairwise('^' + pat))
    init = {'^': 1}
    dp = accum_dp(S, f, op, 0, init)
    return dp.get(pat[-1], 0)


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

pat = 'yukicoder'
ans = solve(pat)
for i in range(len(pat)):
    t = list(pat)
    t[i] = '?'

    ans += solve(''.join(t))
    break

print(ans)