import java.util.*;

public class Main {

  public static void main (String[] args) {

    Scanner sc = new Scanner(System.in);

    int S = sc.nextInt();

    sc.close();

    int f = S / 100;
    int r = S % 100;

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

}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz