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.Scanner;
public class Main {

	public static void main(String[] args) {
	  Scanner sc = new Scanner(System.in);
	   String s = sc.nextLine();
	   String []ss = s.split("");
	   StringBuilder sa = new StringBuilder();
	   StringBuilder sb = new StringBuilder();
	   sa.append(ss[0]); sa.append(ss[1]);
	   sb.append(ss[2]); sb.append(ss[3]);
	   String saa = sa.toString();  String sbb = sb.toString();
	   int a = Integer.parseInt(saa); int b = Integer.parseInt(sbb);
    
	  if(a>=1&&a<=12&&b>=13&&b<=31) {System.out.println("MMYY");}
	  else if(a>=13&&a<=31&&b>=1&&b<=12) {System.out.println("YYMM");}
	  else if(a>=1&&a<=12&&b>=1&&b<=12) {System.out.println("AMBIGUOUS");}
	  else  {System.out.println("NA");}
	
	}

}