Branches, C. Gutierrez

lib/tree.rb

@@ -1,64 +1,177 @@
 class TreeNode
   attr_reader :key, :value
   attr_accessor :left, :right
-
-   def initialize(key, val)
+  
+  def initialize(key, val)
     @key = key
     @value = val
     @left = nil
     @right = nil
-   end
+  end
 end
 
 class Tree
   attr_reader :root
   def initialize
     @root = nil
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+  
+  # Time Complexity: O(log n)
+  # Space Complexity: O(n)
   def add(key, value)
-    raise NotImplementedError
+
+    current = @root 
+    temp = TreeNode.new(key, value) 
+
+    if @root == nil 
+      @root = temp
+      return
+
+    else
+      add_helper(@root, temp)
+    end
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+
+  def add_helper(current_node, temp)
+    if current_node == nil
+      return temp
+    end
+
+    if temp.key < current_node.key 
+      current_node.left = add_helper(current_node.left, temp)
+    else
+      current_node.right = add_helper(current_node.right, temp)
+    end
+    return current_node
+  end
+
+  # Time Complexity: O(log n)
+  # Space Complexity: O(n)
   def find(key)
-    raise NotImplementedError
+    current = @root
+    if current == nil
+      return nil
+    elsif current.key == key
+      return current.value
+    else
+      find_helper(current, key)
+    end
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+
+  def find_helper (current, key) 
+    if current.key == key
+      return current.value
+    elsif current.key > key && current.left != nil 
+      find_helper(current.left, key)
+    elsif current.key > key
+      return nil
+    elsif current.key < key && current.right != nil
+      find_helper(current.right, key)
+    elsif current.key < key
+      return nil
+    end
+  end
+
+  # Time Complexity: O(n)
+  # Space Complexity: O(n)
   def inorder
-    raise NotImplementedError
+    if @root == nil
+      return []
+    end
+    inorder_helper(@root, [])
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+
+  def inorder_helper(current_node, list)
+
+    if current_node == nil
+      return list
+    end
+
+    inorder_helper(current_node.left, list)
+    list.push({key: current_node.key, value: current_node.value})
+    inorder_helper(current_node.right, list)
+    return list
+  end
+
+  # Time Complexity: O(n)
+  # Space Complexity: O(n)
   def preorder
-    raise NotImplementedError
+    if @root == nil
+      return []
+    else
+      return preorder_helper(@root, [])
+    end
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+
+  def preorder_helper(current_node, list)
+    if current_node == nil
+      return list
+    end
+
+    list.push({key: current_node.key, value: current_node.value})
+    preorder_helper(current_node.left, list)
+    preorder_helper(current_node.right, list)
+
+    return list
+  end
+
+  # Time Complexity: O(n)
+  # Space Complexity: O(n)
   def postorder
-    raise NotImplementedError
+    if @root == nil
+      return []
+    else
+      return postorder_helper(@root, [])
+    end
   end
-
-  # Time Complexity: 
-  # Space Complexity: 
+
+  def postorder_helper(current_node, list)
+    if current_node == nil
+      return list
+    end
+
+    postorder_helper(current_node.left, list)
+    postorder_helper(current_node.right, list)
+    list.push({key: current_node.key, value: current_node.value})
+
+    return list
+  end
+
+  # Time Complexity: O(n)
+  # Space Complexity: O(n)
   def height
-    raise NotImplementedError
+    if @root == nil
+      return 0
+    elsif @root.left == nil && @root.right == nil
+      return 1
+    end
+
+    return height_helper(@root)
+
   end
-
+
+  def height_helper(current_node)
+
+    if current_node == nil
+      return 0
+    end
+
+    left = height_helper(current_node.left)
+    right = height_helper(current_node.right)
+    if left > right
+      return left + 1
+    else
+      return right + 1
+    end
+  end
+
   # Optional Method
   # Time Complexity: 
   # Space Complexity: 
   def bfs
     raise NotImplementedError
   end
-
+  
   # Useful for printing
   def to_s
     return "#{self.inorder}"

test/test_helper.rb

@@ -1,10 +1,11 @@
 
-require "minitest"
-require "minitest/autorun"
-require "minitest/reporters"
-require "minitest/skip_dsl"
-
-
-Minitest::Reporters.use! Minitest::Reporters::SpecReporter.new
-
-require_relative "../lib/tree"
+  require "minitest"
+  require "minitest/autorun"
+  require "minitest/reporters"
+  require "minitest/skip_dsl"
+
+
+  Minitest::Reporters.use! Minitest::Reporters::SpecReporter.new
+
+  require_relative "../lib/tree"
+