import sys
input = sys.stdin.readline


def main():
    S = input().rstrip()
    target = 'yukicoder'
    ok = 0
    ng = len(S) // len(target)
    while abs(ok - ng) > 1:
        mid = (ok + ng) // 2
        if target * mid in S:
            ok = mid
        else:
            ng = mid
    print(ok)


main()