如何在Haskell中获取列表中的元组数

Question

我想在列表中得到tupples的总和.举个例子

[("Isuru1","Ranasinghe1",123),("Isuru2","Ranasinghe2",123),("Isuru3","Ranasinghe3",123),("Isuru4","Ranasinghe4",123)]

在上面的列表中答案必须是4.请帮我解决这个问题.我是哈斯克尔新手:(

Answer 1

使用该length功能.它获取任何列表的长度,无论其中包含什么.

例:

Prelude> length [("Isuru1","Ranasinghe1",123),("Isuru2","Ranasinghe2",123),("Isuru3","Ranasinghe3",123),("Isuru4","Ranasinghe4",123)]
4