URL

https://leetcode.com/problems/binary-tree-inorder-traversal/description/?envType=daily-question&envId=2023-12-09

Code

https://github.com/syohex/dotnet-study/blob/master/fsharp/leetcode/challenge/202312/binary_tree_inorder_traversal/main.fsx

type Tree =
    | Leaf
    | Node of int * Tree * Tree

let inorderTraversal (root: Tree) : int list =
    let rec inorderTraversal' node acc =
        match node with
        | Leaf -> acc
        | Node(v, left, right) ->
            let acc' = inorderTraversal' left acc
            inorderTraversal' right (v :: acc')

    inorderTraversal' root [] |> List.rev