a='yukicoder'
s=input()
ind=0
ans = []
g=-1
for i in range(len(s)):
    if i <= g:
        continue
    if s[i] == 'y':
        f = 0
        for j in range(1,len(a)):
            if i + j >= len(s):
                f = 1
                break
            if s[i+j] != a[j]:
                f = 1
                break
        if f == 0:
            ans.append(a)
            g=i+len(a)-1
        else:
            ans.append(0)
            
    else:
        ans.append(0)
    
A=0
cnt=0
for i in range(len(ans)):
    if ans[i] == a:
        cnt+=1
    else:
        A=max(A,cnt)
        cnt=0
        
print(max(A,cnt))