摘要:
Haskell学习笔记--scanl/scanr 类似foldl/flodr 但是将每一步都记录下来,保存为list scanl :: (b -> a -> b) -> b -> [a] -> [b] scanr :: (a -> b -> b) -> b -> [a] -> [b] eg. sca 阅读全文
摘要:
Haskell学习笔记--foldl/flodr foldl :: (b->a->b)->b->[a]->b f x y x0 [y_i] result foldl f v [] = v foldl f v (x:xs) = foldl f (f v x) xs 可以理解为从从头到尾使用 f fol 阅读全文