import java.util.*;
class Main{
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		int s=sc.nextInt();
	
		int l=s/100;
		int r=s%100;
		String ans="NA";


		if(0<l&&l<13&&0<r&&r<13)ans="AMBIGUOUS";
		if(0<l&&l<13&&(r<1||12<r))ans="MMYY";
		if((l<1||12<l)&&0<r&&r<13)ans="YYMM";
		
		System.out.println(ans);
	}
}
/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