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: Accepted)

import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        String str;
        str = sc.next();
        char[] c = str.toCharArray();
        char[] x1 = {c[0],c[1]};
        char[] x2 = {c[2],c[3]};
        boolean b1 = check(Integer.parseInt(new String( x1)));
        boolean b2 = check(Integer.parseInt(new String( x2)));
        
        String ans = "";
        
        if(b1 && b2){
            ans = "AMBIGUOUS";
        }else if(b1){
            ans = "MMYY";
        }else if(b2){
            ans = "YYMM";
        }else{
            ans = "NA";
        }
        System.out.println(ans);
        
        
    }
   static boolean check(int i){
        if(i > 0 && i < 13){
            return true;
        }
        return false;
    }
}