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 JavaScript (node.js v5.12) (judge verdict: Accepted)

function Main(input){
  var S = input.split("");
  var a = S.splice(0,2);
  var lef = a.join("");
  var rig = S.join("");
  lef = parseInt(lef,10);
  rig = parseInt(rig,10);
  
  if((0<lef&&lef<=12)&&rig>12){
    console.log('MMYY');
  }else if(lef>12&&(0<rig&&rig<=12)){
    console.log('YYMM');
  }else if((0<=lef&&lef<=12)&&(0<=rig&&rig<=12)){
    if(lef===0&&rig>0){
      console.log('YYMM');
    }else if(lef>0&&rig===0){
      console.log('MMYY');
    }else if(lef===0&&rig===0){
      console.log('NA');
    }else{
      console.log('AMBIGUOUS');
    }
  }else{
    console.log('NA');
  }



}  

Main(require("fs").readFileSync("/dev/stdin", "utf8"));