import java.util.Scanner;

public class Main {

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

		int i1 = ym/100;
		int i2 = ym%100;
		if(i1 >= 1 && i1 <= 12){
			if(i2 >= 1 && i2 <=12){
				System.out.println("AMBIGUOUS");
			}else{
				System.out.println("MMYY");
			}
		}else{
			if(i2 >= 1 && i2 <=12){
				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