import sys
def input(): return sys.stdin.readline().rstrip()


def main():
    S = input()
    lo = 0
    hi = len(S)//9+1
    while lo+1 != hi:
        mi = (lo+hi)//2
        if S.find('yukicoder'*mi) != -1:
            lo = mi
        else:
            hi = mi
    print(lo)


if __name__ == '__main__':
    main()