S = input()
N, Ans, C, I = len('yukicoder'), 0, 0, 0
while I+N <= len(S):
    if S[I:I + N] == 'yukicoder':
        C += 1
        I += N
    else:
        Ans = max(Ans, C)
        C = 0
        I += 1
print(max(Ans, C))