import java.util.Scanner;
 
public class Main {
 
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int s = Integer.parseInt(sc.next());
		int L = s / 100;
		int R = s % 100;
		if (1 <= L && L <= 12) {
			if (1 <= R && R <= 12)
				System.out.println("AMBIGUOUS");
			else
				System.out.println("MMYY");
		} else {
			if (1 <= R && R <= 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