﻿ ABC126 B - YYMM or MMYY - Atcoder

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Score : $200$ points

### Problem Statement

You have a digit sequence $S$ of length $4$. You are wondering which of the following formats $S$ is in:

• YYMM format: the last two digits of the year and the two-digit representation of the month (example: 01 for January), concatenated in this order
• MMYY format: the two-digit representation of the month and the last two digits of the year, concatenated in this order

If $S$ is valid in only YYMM format, print YYMM; if $S$ is valid in only MMYY format, print MMYY; if $S$ is valid in both formats, print AMBIGUOUS; if $S$ is valid in neither format, print NA.

### Constraints

• $S$ is a digit sequence of length $4$.

### Input

Input is given from Standard Input in the following format:

$S$


### Output

Print the specified string: YYMM, MMYY, AMBIGUOUS or NA.

### Sample Input 1

1905


### Sample Output 1

YYMM


May $XX19$ is a valid date, but $19$ is not valid as a month. Thus, this string is only valid in YYMM format.

### Sample Input 2

0112


### Sample Output 2

AMBIGUOUS


Both December $XX01$ and January $XX12$ are valid dates. Thus, this string is valid in both formats.

### Sample Input 3

1700


### Sample Output 3

NA


Neither $0$ nor $17$ is valid as a month. Thus, this string is valid in neither format.