import java.util.*;

public class Main{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        
        int s = sc.nextInt();

        int s1 = s / 100;
        int s2 = s - (s1 * 100);

        if (s1 > 0 && s1 <= 12 && s2 > 0 && s2 <= 12)
            System.out.println("AMBIGUOUS");
        else if (s1 > 0 && s1 <= 12)
            System.out.println("MMYY");
        else if (s2 > 0 && s2 <= 12)
            System.out.println("YYMM");
        else
            System.out.println("NA");
        sc.close();
    }
}
/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