import sys
#input = sys.stdin.readline
#input = sys.stdin.buffer.readline
import copy

def main():
    N = int(input()); MOD = pow(10,9) + 7
    S = input()
    Y = "yukicoder"
    T = [Y]
    for i in range(9):
        temp = Y[:i] + "?" + Y[i+1:]
        T.append(temp)
    #print(T)
    ans = 0
    for t in T:
        #print(t)
        #i番目まで一致している場合の数
        dp = [0]*10
        dp[0] = 1
        for i in range(N):
            p = copy.copy(dp)
            dp,p = p,dp
            for j in range(9):
                if S[i] == t[j]:
                    dp[j+1] += p[j]
                    dp[j+1] %= MOD
            #print(dp)
        ans += dp[9]
        ans %= MOD
    print(ans)





if __name__ == '__main__':
    main()