import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);       
		int n = sc.nextInt();
        int judge = 0;
        if(n%100>0 && n%100<=12){judge++;}
        if(n/100>0 && n/100<=12){judge+=2;}
		if(judge==0){System.out.println("NA");}
        if(judge==1){System.out.println("YYMM");}
        if(judge==2){System.out.println("MMYY");}
        if(judge==3){System.out.println("AMBIGUOUS");}
  }
}

/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