s = int(input())
a = s // 100
b = s % 100

if 1 <= a <= 12 and 1 <= b <= 12:
    print("AMBIGUOUS")
elif 1 <= a <= 12:
    print("MMYY")
elif 1 <= b <= 12:
    print("YYMM")
else:
    print("NA") s = int(input()) s int(input()) int input() input a = s // 100 a s // 100 s 100 b = s % 100 b s % 100 s 100 if 1 <= a <= 12 and 1 <= b <= 12:
    print("AMBIGUOUS")
elif 1 <= a <= 12:
    print("MMYY")
elif 1 <= b <= 12:
    print("YYMM")
else:
    print("NA") 1 <= a <= 12 and 1 <= b <= 12 1 <= a <= 12 1 <= a 1 a 12 1 <= b <= 12 1 <= b 1 b 12 print("AMBIGUOUS") print "AMBIGUOUS" elif 1 <= a <= 12:
    print("MMYY") 1 <= a <= 12 1 <= a 1 a 12 print("MMYY") print "MMYY" elif 1 <= b <= 12:
    print("YYMM") 1 <= b <= 12 1 <= b 1 b 12 print("YYMM") print "YYMM" print("NA") print "NA" a = s // 100 s // 100 a s = int(input()) int(input()) s b = s % 100 s % 100 b
s = int(input())
a = s // 100
b = s % 100

if 1 <= a <= 12 and 1 <= b <= 12:
    print("AMBIGUOUS")
elif 1 <= a <= 12:
    print("MMYY")
elif 1 <= b <= 12:
    print("YYMM")
else:
    print("NA")