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>

#define rep(i, a, n)  for(ll i=a; i<n; i++)
#define per(i, a, n)  for(ll i=n-1; i>=a; i--)
#define fill0(n)  setfill('0') << right << setw(n)
#define all(x)  (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define LONGMAX 1e18
#define INTMAX 1000000000
using namespace std;
typedef long long ll;
// typedef pair<ll,ll> p;

string s;
bool flag1, flag2;

int main(){
  cin >> s;
  int tmp1 = stoi(s.substr(0,2));
  if (tmp1 > 0 and tmp1 < 13){
    flag1 = true;
  }

  int tmp2 = stoi(s.substr(2,2));
  if (tmp2 > 0 and tmp2 < 13){
    flag2 = true;
  }

  if(tmp1 == 0 or tmp2 == 0 ){
    flag1 = false;
    flag2 = false;
  }
  if(flag1){
    if(flag2) cout << "AMBIGUOUS" << endl;
    else cout << "MMYY" << endl;
  } else{
    if(flag2) cout << "YYMM" << endl;
    else cout << "NA" << endl;
  }
}