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>
int m;
char s[4];
int main(void)
{
    scanf("%s", s);
    if (s[0] == '0' && s[1] >= '1' || s[0] == '1' && s[1] <= '2')
    {
        m = 1;
    }
    else
    {
        m = 2;
    }

    if (m == 1)
    {
        if (s[2] == '0' && s[3] >= '1' || s[2] == '1' && s[3] <= '2')
        {
            printf("AMBIGUOUS");
        }
        else
        {
            printf("MMYY");
        }
    }
    else
    {
        if (s[2] == '0' && s[3] == '0' || s[2] >= '2' || s[2] == '1' && s[3] >= '3')
        {
            printf("NA");
        }
        else
        {
            printf("YYMM");
        }
    }
    return 0;

    /*if(s[0] =='0'&&s[1] == '0'||s[2] =='0'&&s[3] == '0'){
       printf("NA");
    }else
    if (s[0] >= '2')
    {
        printf("YYMM");
    }
    else if (s[1] >= '3')
    {
        printf("YYMM");
    }
    else if(s[2] >= '2'&&s[3] >= '3'){
        printf("MMYY");
    }else {
        printf("AMBIGUOUS");
    }*/
}