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<string.h>
#include<stdlib.h>

int main(){
  int i,j,k;
  char S[4];
  scanf("%d",&k);
  int A,B;
  /*A=(S[0]*10+atoi(S[1]);
  B=atoi(S[2])*10+atoi(S[3]);*/
  
  A = k /100;
  B = k % 100;
  
  if(A >= 1 && A<=12){
    if(B >= 1 && B<=12){
      puts("AMBIGUOUS");
      return 0;
    }
    else if(B>=13){
      puts("MMYY");
      return 0;
    }
  }
  /*else if(A>=13){
    if(B >= 1 && B<=12){
      puts("YYMM");
      return 0;
    }
    else{
      puts("NA");
      return 0;
    }
  }*/
  else if(B >=1 && B <= 12){
    if(A>=1){
      puts("YYMM");
      return 0;
    }
  }
  puts("NA");
  return 0;
}