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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using static System.Math;
using static System.Console;

namespace B_ABC126
{
    class MainClass
    {

        static int[] s;


        public static void Main(string[] args)
        {
            s = Array.ConvertAll(ReadLine().Split().ToArray(), int.Parse);
            int mae = s[0]/100;
            int ushiro = s[0]%100;
            string ans="";
            if(mae>=1&&12>=mae){
                if(ushiro>=1&&ushiro<=12){
                    ans = "AMBIGUOUS";

                }else{
                    ans = "MMYY";
                }
            }else{
                if(ushiro>=1&&ushiro<=12){
                    ans = "YYMM";
                }else{
                    ans = "NA";
                }
            }

            WriteLine(ans);

        }
    }
}