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 Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
public class Main{
  public static void main(String[]args){
      Scanner sc = new Scanner(System.in);

     String s = sc.next();
     char[] c = new char[4];
     int[] a = new int[4];

     for (int i = 0;i<4 ;i++ ) {
       c[i] = s.charAt(i);
     }

     for (int i = 0;i<4 ;i++ ) {
       String sn = String.valueOf(c[i]);
       a[i] =  Integer.parseInt(sn);
     }

     if (a[0]*10+a[1]<=12) {
       if (a[2]*10+a[3]<=12) {
         System.out.println("AMBIGUOUS");
         System.exit(0);
       }
     }

     if (a[2]*10+a[3]<=12&&a[2]*10+a[3]>0) {
        System.out.println("YYMM");
     }else if(a[0]*10+a[1]<=12&&a[0]*10+a[1]>0){
       System.out.println("MMYY");
     }else{
       System.out.println("NA");
     }


      }
    }