AS Arrow

AS refer to Add and Sub. During the game process, the card present as Arrow.
Rule:
Delete all card to win. User can drag and drop card from cards library to original
6 cards. At the game start, original 6 cards look like:

d
-b
e- a
-c
f

User can connect d, e, f cards. Once d and e are deleted, user can connect to b.
Cards are positive for a, b, c, d, e, f. And then connecting card is negative.
In the similar way, the next card is positive (add/plus), and then the card is negative
(subtract/minus). The row of cards can be deleted as sum (add/subtract) of cards is 0. (J is 11,Q is 12, K is 13)
If the number of cards is 12, but can't be deleted now.
The game is over. By the way, if cards library is empty and user can't win,
the game is over.
v0.1.1 Update:
You can move an entire pile to another pile (except the first card).
If the front half of a pile becomes 0 after applying + / −, you must click the next card pile (the card immediately after that 0) to auto-remove