import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int num = sc.nextInt();
        int first = num / 100;
        int second = num - (first * 100);
        if((first < 1 || first > 12) && (second >= 1 && second <= 12)) System.out.println("YYMM");
        else if((second < 1 || second > 12) && (first >= 1 && first <= 12)) System.out.println("MMYY");
        else if((first >= 1 && first <= 12) && (second >= 1 && second <= 12)) System.out.println("AMBIGUOUS");
        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