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

//関数宣言
//int func(int x, int y);

int main(void){

  //文字列入力
  char str[5];
  scanf("%s", str);

  int num;
  num = atoi(str);

  int fst,snd;

  fst = num/100;
  snd = num%100;

  /* printf("%d %d\n", fst, snd); */

  int YM=0,MY=0;

  if(fst >= 1 && fst <= 12){
    MY=1;
  }
  if(snd >= 1 && snd <= 12){
    YM=1;
  }

  if(MY){
    if(YM){
      printf("AMBIGUOUS\n");
    }else{
      printf("MMYY\n");
    }
  }else{
    if(YM){
      printf("YYMM\n");
    }else{
      printf("NA\n");
    }
  }

  return 0;
}