COCI '22 Contest 3 #1 Estimathon
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Paula and Domagoj are organizing an exciting team competition called Estimathon. They have already prepared the questions, and now they are arranging the room for the quiz.
Before you could blink, Domagoj had already placed  tables in the room. Now
they need to add chairs. They have very colourful chairs. They come in 
 colours,
and there are 
 chairs of the 
-th colour. Every team consists of four people.
Therefore, for each table, Paula and Domagoj need to add four chairs. They want
to make the room look as nice as possible. To make that happen, they agreed on these conditions:
- Each table has all chairs of the same colour
 - Every chair colour is used; that is, for every colour, there exists at least one table that has chairs of that colour
 
Caring too much about how nice the room will look, they suddenly realized that the quiz would start very soon! Help them find out if a chair arrangement with these conditions is even possible.
Input Specification
The first line contains integers  and 
 
, the number of tables and the number of chair
colours.
The second line contains  integers 
 
, where the 
-th number is the number of chairs of
the 
-th colour.
Output Specification
In the first and only line, output DA if it is possible to arrange the chairs so that both conditions hold; otherwise, output NE.
Constraints
| Subtask | Points | Constraints | 
|---|---|---|
| No additional constraints. | 
Sample Input 1
7 3
5 21 9
Sample Output 1
DA
Sample Input 2
5 4
8 5 10 3
Sample Output 2
NE
Explanation for Sample 2
We can have  tables with chairs of the same colour, but we cannot have a table with colour 
, so the second condition can't be satisfied.
Sample Input 3
6 5
5 5 5 5 5
Sample Output 3
NE
                    
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