from sys import stdin, stdout
input = lambda: stdin.readline().rstrip()
println = stdout.write

def main():
    S = input()
    B = stdin.read()

    if S == 'oda':
        player = ('oda\n', 'yukiko\n')
    else:
        player = ('yukiko\n', 'oda\n')

    stone = 64 - B.count('.')
    println(player[stone % 2])

main()