practice

fromScalaConsole.scala

trait Tree 

case object Empty extends Tree

case class Node(i: Int, left:Tree, right:Tree) extends Tree

def show(tree: Tree) : String  // implement this method

/* Test Cases

show(Node(7, Node(3, Empty, Empty), Node(7, Empty, Empty)))

output:

7
|--3
`--7

*/
/*
show(Node(7,
          (Node 2 
                (Node 1 Empty Empty) 
                (Node 4 
                      (Node 3 Empty Empty) 
                      (Node 6 Empty Empty))) 
          (Node 8 
                Empty 
                (Node 21 
                      (Node 12 
                            Empty 
                            Empty) 
                      (Node 23 
                            Empty 
                            Empty)))
output:

7
|--2
|  |--1
|  `--4
|     |--3
|     `--6
`--8
   `--21
      |--12
      `--23
*/