s=input()
sum_a=0
sum_b=0
flag=0
for ch in s:
    if ch=='a':
        sum_a+=1
    elif ch=='b':
        sum_b+=1
    if sum_a<sum_b:
        flag=1

if flag==0 and sum_a==sum_b:
    print('Good')
    
else:
    print('Bad')