s = input()
B = ""
for i in range(8):
    B += input()

#先行s, 後攻k
if s == "oda":
    k = "yukiko"
else:
    k = "oda"

osero = B.count("b") + B.count("w")

#オセロの数が偶数なら次は先行、奇数なら次は後攻
if osero % 2 == 0:
    print(s)
else:
    print(k)