import java.util.Scanner;

class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int input = sc.nextInt();
        int first = input / 100;
        int latter = input % 100;

        boolean firstMonth = first > 0 && first <= 12;
        boolean latterMonth = latter > 0 && latter <= 12;
        if(firstMonth && latterMonth)System.out.println("AMBIGUOUS");
        else if(firstMonth)System.out.println("MMYY");
        else if(latterMonth)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