Problem:
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.

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define ll long long
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	string s;
	cin >> s;
	int a=0,vv=0;
	
	if((s[0]=='1' && s[1]<='2') || (s[0]=='0' && s[1]!='0'))
	{
		a=1;
	}
	if((s[2]=='1' && s[3]<='2') || (s[2]=='0' && s[3]!='0'))
	{
		vv=1;
	}
	if(a==1 && vv!=1)
	{
		cout << "MMYY";
	}
	else if(a==1)
	{
		cout << "AMBIGUOUS";
	}
	else if(vv==1)
	{
		cout << "YYMM";
	}
	else
	{
		cout << "NA";
	}
	return 0;
}