// insert insert a node to tree.
insert insert a node to tree.
// insert insert a node to tree .
func (b *BST) insert(key int) {
	if b.Root == nil {
		b.Root = &Node{
			Key:   key,
			Left:  nil,
			Right: nil,
		}
	} else {
		recursiveInsert(b.Root, &Node{
			Key:   key,
			Left:  nil,
			Right: nil,
		})
	}
}
func ( b * BST ) insert ( key int ) { if b . Root == nil { b . Root = & Node { Key : key , Left : nil , Right : nil , } } else { recursiveInsert ( b . Root , & Node { Key : key , Left : nil , Right : nil , } ) } }
insert insert a node to tree.
insert insert a node to tree .