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 (Clang 3.8.0) (judge verdict: Accepted)

#include<stdio.h>
#include<string.h>
#define FR(N) for(int i = 0;i < N;i++)
#define PR(N) printf("%s\n",N);
int main(void){
  int n;
  scanf("%d",&n);
  int a = n / 100,b = n % 100;
  if(0 < a && a < 13 && 0 < b && b < 13){
    PR("AMBIGUOUS");
  }else if((12 < a || a == 0) && 0 < b && b < 13){
    PR("YYMM");
  }else if((12 < b || b == 0) && 0 < a && a < 13){
    PR("MMYY");
  }else{
    PR("NA");
  }
  return 0;
}