N=int(input())
S=input().strip()

mod=10**9+7

DP0=[0]*9
DP1=[0]*9

yukicoder="yukicoder"

for s in S:
    for j in range(9):
        if s==yukicoder[j]:
            if j==0:
                DP0[0]+=1
            else:
                DP0[j]+=DP0[j-1]
                DP1[j]+=DP1[j-1]
    if s=="?":
        DP1[0]+=1
        for j in range(1,9):
            DP1[j]+=DP0[j-1]

    for j in range(9):
        DP0[j]%=mod
        DP1[j]%=mod

print((DP0[-1]+DP1[-1])%mod)