小编Vla*_*scu的帖子

如果我有2个Haskell映射,例如:

[("a",1),
 ("b",2),
 ("c",1)]

和

[("a",1)]

如何以这样的方式编写函数:

[("a",2),("b",2),("c",1)]

到目前为止,我只能编写基本案例,但这就是全部.

我想在haskell中实现一个简单的8off单人纸牌游戏,我不太清楚如何定义我的棋盘,以及如何制作一个返回随机起始板的功能.如何修改myBoard和我的数据结构？到现在为止,我有这些:

data Pip = A|TW0|THREE|FOUR|FIVE|SIX|SEVEN|EIGHT|NINE|TEN|J|Q|K  --pip value
       deriving (Eq,Show)
data Suit = S|H|D|C                                              --suit
       deriving (Eq,Show)
type Card = (Pip,Suit)                                           --card
type Deck = [(Card)]                                             --deck
type Foundations = [(Deck)]                                        foundations
type Columns = [(Deck)]                                          --columns
type Reserve = [(Deck)]                                          --reserve
type EOBoard = [(Deck)]

myBoard::Deck->EOBoard
myBoard pack = [shuffle pack]

返回我,这个:

[[(K,D),(TW0,H),(SEVEN,C),(SEVEN,S),(THREE,D),(NINE,S),(THREE,C),(FOUR,H),(THREE,S),(TW0,D),(TW0,C),(FOUR,S),(K,S),(TEN,D),(J,S),(EIGHT,H),(FOUR,D),(NINE,H),(SEVEN,H),(A,S),(SIX,S),(EIGHT,S),(FIVE,S),(FOUR,C),(K,H),(Q,D),(THREE,H),(TEN,H),(A,D),(EIGHT,C),(NINE,D),(Q,H),(J,D),(J,C),(TEN,C),(Q,S),(Q,C),(J,H),(NINE,C),(SIX,C),(FIVE,H),(SEVEN,D),(A,C),(TW0,S),(EIGHT,D),(FIVE,D),(TEN,S),(K,C),(A,H),(SIX,D),(FIVE,C),(SIX,H)]]

我有一个字符列表,类似于

['t','u','p','l','e']

我想创建一个字符串列表:

['tuple'

我试图初始化一个空数组并追加或+ =但它仍然返回一个字符列表.我如何连接字符串？