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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
#include <string>
#include <vector>
#include <algorithm>
#include <iostream>
#include <set>
using namespace std;
const int MOD = 1000000007;
const int INF = 1e9;
typedef long long ll;

int main(){
    //string s;
    //cin >> s;

    bool yymmflg=0;
    bool mmyyflg=0;


    /*if(!((s[0]=='0' && s[1]!='0')  || s[0]=='1' && (s[1]=='0' || s[1]=='1' || s[1]=='2'))){ //00 13~99 s0s1が
        mmyyflg=0;
    }
    else if(!((s[2]=='0' && s[3]!='0')  || s[2]=='1' && (s[3]=='0' || s[3]=='1' || s[3]=='2'))){
        yymmflg=0;
    }
    else if(s[0]=='0' && s[1]=='0' || s[2]=='0' && s[3]=='0'){
        mmyyflg=0;
        yymmflg=0;
    }


    if(yymmflg==1 && mmyyflg==1){
        cout << "AMBIGUOUS" << endl;
    }
    else if(yymmflg==1 && mmyyflg==0){
        cout << "YYMM" << endl;
    }
    else if(yymmflg==0 && mmyyflg==1){
        cout << "MMYY" << endl;
    }
    else{
        cout << "NA" << endl;
    }*/

    int num;
    cin >> num;

    int head=0;
    int tail=0;

    head = num / 100;
    tail = num % 100;

    if(head == 0 || tail == 0 || (head >= 13 && tail >= 13)){
        cout << "NA" << endl;
        return 0;
    }
    if(head >= 1 && head <= 12 && tail >= 1 && tail <= 12){
        cout << "AMBIGUOUS" << endl;
        return 0;
    }

    if(head >= 1 && head <= 12 && !(tail >= 1 && tail <= 12)){
        cout << "MMYY" << endl;
        return 0;
    }

    if(!(head >= 1 && head <= 12) && tail >= 1 && tail <= 12){
        cout << "YYMM" << endl;
        return 0;
    }
    
    return 0;
}