# Security

S = gets.chomp.to_s
pre = " " #一つ前
cur = " " #現在
ans = "Good"
for i in 0..S.length-1 do
    if i != 0
    pre = S[i-1]
    end
    cur = S[i]
    if i != 0 && cur == pre
        ans = "Bad"
        break
    end
end
puts ans