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 line = sc.nextLine();
    	String[] spl = line.split("");
    	spl[0] += spl[1];
    	spl[2] += spl[3];

    	int fir = Integer.parseInt(spl[0]);
    	int sec = Integer.parseInt(spl[2]);

    	if(fir == 0 || sec == 0){
    		System.out.println("NA");
    		System.exit(0);
    	}

    	if(0 < fir && fir <= 12 && 0 < sec && sec <= 12){
    		System.out.println("AMBIGUOUS");
    	}else if(0 < fir && fir <= 12){
    		System.out.println("MMYY");
    	}else if(0 < sec && sec <= 12){
    		System.out.println("YYMM");
    	}else{
    		System.out.println("NA");
    	}

    }
}