N = int(input())
S = input()
T = 'yukicoder'
mod = 10**9+7
DP = [[[0] * 2 for _ in range(N+1)] for _ in range(10)]
for i in range(N+1):
    DP[0][i][0]=1

for i in range(9):
    for j in range(N):
        if S[j]==T[i]:
            DP[i+1][j+1][0]=(DP[i+1][j+1][0]+DP[i][j][0])%mod
            DP[i+1][j+1][1]=(DP[i+1][j+1][1]+DP[i][j][1])%mod
        if S[j]=='?':
            DP[i+1][j+1][1]=(DP[i+1][j+1][1]+DP[i][j][0])%mod

    for j in range(N):
        DP[i+1][j+1][0]=(DP[i+1][j+1][0]+DP[i+1][j][0])%mod
        DP[i+1][j+1][1]=(DP[i+1][j+1][1]+DP[i+1][j][1])%mod

print(sum(DP[-1][-1])%mod)