import sys
for line in sys.stdin:
password = line
length = len(password)
if length <= 8:
print('NG')
continue
else:
typ = [False, False, False, False]
abc = 'abcdefghijklmnopqrstuvwxyz'
repeat_ = False
for i in range(length-2):
if password[i]+password[i+1]+password[i+2] in password[i+3:]:
repeat_ = True
break
if password[i] in abc:
typ[0] = True
elif password[i] in abc.upper():
typ[1] = True
elif password[i] in '0123456789':
typ[2] = True
else:
typ[3] = True
if repeat_:
print('NG')
elif sum(typ)<3 :
print('NG')
else :
print('OK')