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 <iostream>

using namespace std;
 
int main(void){
	
	char s[4];
	
	cin>>s;
	
	int S[4];
	
	for(int i=0;i<4;i++)
		S[i]=(int)(s[i]-48);
	
	if((S[0]*10+S[1]>=13 && (S[2]*10+S[3]<=12 && S[2]*10+S[3]>=1)) || (S[0]*10+S[1]==0 && (S[2]*10+S[3]<=12 && S[2]*10+S[3]>=1)))
		cout<<"YYMM";
	else if(((S[0]*10+S[1]<=12 && S[0]*10+S[1]>=1) && S[2]*10+S[3]>=13) ||((S[0]*10+S[1]<=12 && S[0]*10+S[1]>=1) && S[2]*10+S[3]==0))
		cout<<"MMYY";
	else if((S[0]*10+S[1]<=12 && S[0]*10+S[1]>=1) && (S[2]*10+S[3]<=12 && S[2]*10+S[3]>=1))
		cout<<"AMBIGUOUS";
	else
		cout<<"NA";
	
	return 0;
}