s = input()
t = 'yukicoder'
n, m = len(s), len(t)

ans = 0
i, now = 0, 0
while i < n:
    if i < n and s[i:i+m] == t:
        now += 1
        ans = max(ans, now)
        i += m
    else:
        now = 0
        i += 1
print(ans)