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: Accepted)

#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef vector<LL> VI;
typedef vector<VI> VVI;
typedef pair<LL, LL> PII;
typedef vector<string> VS;
inline LL toInt(string s) {LL v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
#define PB push_back
#define MP make_pair
#define SZ(a) LL((a).size())
#define EACH(x,c) for(auto x: (c))
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define ALL(c) (c).begin(), (c).end()
#define REVERSE(c) reverse(ALL(c))
#define SORT(c) sort(ALL(c))
#define RSORT(c) sort((c).rbegin(),(c).rend())
#define STABLE_SORT(c) stable_sort(ALL(c))
#define STABLE_RSORT(c) stable_sort((c).rbegin(),(c).rend())
#define UNIQUE(c) SORT(c); (c).erase(unique(ALL(c)), (c).end());
#define FOR(i,a,b) for(LL i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
const double INF = 1e7;
const double EPS = 1e-10;
const double PI  = acos(-1.0);
#define dump(x)  cerr << #x << " = " << (x) << endl;


int main() {
	string S;
    cin >> S;
    LL x = toInt(S);
    LL f = x / 100, l = x % 100;
    LL flag = 0;
    if (1 <= f && f <= 12) {
        if (1 <= l && l <= 12) {
            cout << "AMBIGUOUS" << endl;
        } else {
            cout << "MMYY" << endl;
        }
    } else {
        if (1 <= l && l <= 12) {
            cout << "YYMM" << endl;
        } else {
            cout << "NA" << endl;
        }
    }
	
    return 0;
}