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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
 
int main() {
  int count = 0;
  
  char s[4];
  scanf("%s", s);
  
  int c1, c2;
  c1 = ((int)s[0]*10 + (int)s[1]);
  c2 = ((int)s[2]*10 + (int)s[3]);
    
  if(c1 == 0 && c2 == 0){
    printf("NA\n");
    count += 1;
  }
  if(c1 == 0 && c2 != 0){
    if(c2 <= 12){
      printf("YYMM\n");
    } else {
      printf("NA\n");
    }
    count += 1;
  }
  
  if(c1 != 0 && c2 == 0){
    if(c1 <= 12){
      printf("MMYY\n");
    } else {
      printf("NA\n");
    }
    count += 1;
  }
  
  if(count == 0){
    if(c1 <= 12 && c2 <= 12){
      printf("AMBIGUOUS\n");
  } else if(c1 <= 12 && c2 > 12){
      printf("MMYY\n");
  } else if(c1 > 12 && c2 <= 12){
      printf("YYMM\n");
  } else if(c1 > 12 && c2 > 12){
      printf("NA\n");
  }
  }
  return 0;
}