// recursiveInOrderTraverse traverse tree by in-order recursively.
recursiveInOrderTraverse traverse tree by in-order recursively.
// recursiveInOrderTraverse traverse tree by in - order recursively .
func recursiveInOrderTraverse(n *Node) {
	if n != nil {
		recursiveInOrderTraverse(n.Left)
		fmt.Printf("%d\n", n.Key)
		recursiveInOrderTraverse(n.Right)
	}
}
func recursiveInOrderTraverse ( n * Node ) { if n != nil { recursiveInOrderTraverse ( n . Left ) fmt . Printf ( " \n " , n . Key ) recursiveInOrderTraverse ( n . Right ) } }
recursiveInOrderTraverse traverse tree by in-order recursively.
recursiveInOrderTraverse traverse tree by in - order recursively .