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 Scala (2.11.7) (judge verdict: Accepted)

object Main {
  def main(args: Array[String]): Unit = {
    val array = Array("YYMM", "MMYY", "AMBIGUOUS", "NA")
    val sc = new java.util.Scanner(System.in)
    val nk = sc.nextLine()
    val f = nk.substring(0, 2)
    val l = nk.substring(2, 4)
    val fb = f.toInt >= 1 && f.toInt < 13
    val lb = l.toInt >= 1 && l.toInt < 13

    if (fb && lb) { println(array(2)) }
    else if (!fb && !lb){ println(array(3)) }
    else if (!fb && lb) { println(array(0)) }
    else if (fb && !lb) { println(array(1)) }
  }
}