import java.io.*;
import java.util.*;

public class Main {

    public static void main(final String[] args) throws Exception {
        final Scanner sc = new Scanner(System.in);
        long S;
        S = sc.nextLong();

        final Solver solver = new Solver();
        System.out.println(solver.solve(S));
    }
}

class Solver {
    public String solve(long S) {
        long first = S / 100;
        long second = S % 100;

        if ((first >= 1 && first <= 12) && (second >= 1 && second <= 12)) {
            return "AMBIGUOUS";
        }

        if (first >= 1 && first <= 12) {
            return "MMYY";
        }

        if (second >= 1 && second <= 12) {
            return "YYMM";
        }

        return "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