Traverse Binary Tree

[cd155]

All the traverse in the following code can be shortened. It is unnecessary to specifically make left or right to be Null. It better treat them just as children as left and right.

algorithm-design-with-haskell/src/Tree.hs

Line 45 in 71661bb

inOrderTraverse :: BiTree a -> [a]

[cd155]

New binary tree traverses are made in the following link.

https://github.com/cd155/haskell-leetcode/blob/ee5518093d234f2261aebb185421239c56d6eaa2/main/WeekOne.hs#L426-L439