s = input()
if 1 <= int(s[:2]) <= 12 and 1 <= int(s[2:]) <= 12:
  print("AMBIGUOUS")
elif 1 <= int(s[:2]) <= 12:
  print("MMYY")
elif 1 <= int(s[2:]) <= 12:
  print("YYMM")
else:
  print("NA") s = input() s input() input if 1 <= int(s[:2]) <= 12 and 1 <= int(s[2:]) <= 12:
  print("AMBIGUOUS")
elif 1 <= int(s[:2]) <= 12:
  print("MMYY")
elif 1 <= int(s[2:]) <= 12:
  print("YYMM")
else:
  print("NA") 1 <= int(s[:2]) <= 12 and 1 <= int(s[2:]) <= 12 1 <= int(s[:2]) <= 12 1 <= int(s[:2]) 1 int(s[:2]) int s[:2] s :2 2 12 1 <= int(s[2:]) <= 12 1 <= int(s[2:]) 1 int(s[2:]) int s[2:] s 2: 2 12 print("AMBIGUOUS") print "AMBIGUOUS" elif 1 <= int(s[:2]) <= 12:
  print("MMYY") 1 <= int(s[:2]) <= 12 1 <= int(s[:2]) 1 int(s[:2]) int s[:2] s :2 2 12 print("MMYY") print "MMYY" elif 1 <= int(s[2:]) <= 12:
  print("YYMM") 1 <= int(s[2:]) <= 12 1 <= int(s[2:]) 1 int(s[2:]) int s[2:] s 2: 2 12 print("YYMM") print "YYMM" print("NA") print "NA" s = input() input() s
s = input()
if 1 <= int(s[:2]) <= 12 and 1 <= int(s[2:]) <= 12:
  print("AMBIGUOUS")
elif 1 <= int(s[:2]) <= 12:
  print("MMYY")
elif 1 <= int(s[2:]) <= 12:
  print("YYMM")
else:
  print("NA")