from collections import deque
S = input()
N = len(S)
que = deque()
for s in S:
    que.append(s)
    
#print(que)

ans = 0
count = 0
for i in range(N):
    if len(que) >= 9:
        check = que[0]+que[1]+que[2]+que[3]+que[4]+que[5]+que[6]+que[7]+que[8]
        if check == 'yukicoder':
            count += 1
            ans = max(ans, count)
            for j in range(9):
                que.popleft()
        else:
            que.popleft()
            count = 0
    else:
        break
print(ans)