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: Accepted)

#include<stdio.h>
#include<string.h>

int main(){
  char month[12][2]={"01","02","03","04","05","06","07","08","09","10","11","12"};
  char s[4];
  int i,c1=0,c2=0;
  scanf("%s",s);
  for(i=0;i<12;i++){
    if(strncmp(s,month[i],2)==0)
      c1++;
    if(strncmp(&*(s+2),month[i],2)==0)
      c2++;
  }
  if(c1==1 && c2==1)
    printf("AMBIGUOUS\n");
  else if(c1==1 && c2==0)
    printf("MMYY\n");
  else if(c1==0 && c2==1)
    printf("YYMM\n");
  else
    printf("NA\n");
  return 0;
}