Problem:
Score : 200 points

Problem Statement

You have a digit sequence S of length 4. You are wondering which of the following formats S is in:

YYMM format: the last two digits of the year and the two-digit representation of the month (example: 01 for January), concatenated in this order

MMYY format: the two-digit representation of the month and the last two digits of the year, concatenated in this order

If S is valid in only YYMM format, print YYMM; if S is valid in only MMYY format, print MMYY; if S is valid in both formats, print AMBIGUOUS; if S is valid in neither format, print NA.

Constraints

S is a digit sequence of length 4.

Input

Input is given from Standard Input in the following format:

S

Output

Print the specified string: YYMM, MMYY, AMBIGUOUS or NA.

Sample Input 1

1905

Sample Output 1

YYMM

May XX19 is a valid date, but 19 is not valid as a month. Thus, this string is only valid in YYMM format.

Sample Input 2

0112

Sample Output 2

AMBIGUOUS

Both December XX01 and January XX12 are valid dates. Thus, this string is valid in both formats.

Sample Input 3

1700

Sample Output 3

NA

Neither 0 nor 17 is valid as a month. Thus, this string is valid in neither format.

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

#-*- coding: utf-8 -*-
"""
oj dl https://atcoder.jp/contests/abc116/tasks/abc116_d -d test-d
oj test -d test-d -c "python abc116d.py"
oj test -d test-d -c "python abc116d.py" test-d/sample-3.in
"""
from collections import defaultdict
import sys
import math
from datetime import datetime
import re

def sol(S):
    #YYMM, MMYY, AMBIGUOUS, NA のうち正しいものを出力せよ。
    if re.match("^[0-1][0-2][0-1][0-2]$", S):
        return 'AMBIGUOUS'
    elif re.match("^[0-9][0-9][1][0-2]$", S):
        return 'YYMM'
    elif re.match("^[0-9][0-9][0][1-9]$", S):
        return 'YYMM'
    elif re.match("^[1][0-2][0-9][0-9]$", S):
        return 'MMYY'
    elif re.match("^[0][1-9][0-9][0-9]$", S):
        return 'MMYY'
    else:
        return 'NA'


do_submit = True
#do_submit = False

def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    # n = int(parsed_lines[0][0])
    # k = int(parsed_lines[0][1])
    S = parsed_lines[0][0]
    return S


if not do_submit:
    S = input_parse("""
    1905
    """)
    print(sol(S))

    S = input_parse("""
    0112
    """)
    print(sol(S))

    S = input_parse("""
    1700
    """)
    print(sol(S))



else:
    #n, k = list(map(int, input().split()))
    S = input()
    print(sol(S))

    # S = input().strip()
    # print(sol(S))