From 89d0fa1f32fcc7e6c9b5552bd189d0b502ced6b4 Mon Sep 17 00:00:00 2001 From: Beatrice T Date: Sun, 4 Apr 2021 20:38:02 -0700 Subject: [PATCH 1/4] this is a commitment message --- lib/tree.rb | 58 ++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 48 insertions(+), 10 deletions(-) diff --git a/lib/tree.rb b/lib/tree.rb index c0d4b51..c64ba23 100644 --- a/lib/tree.rb +++ b/lib/tree.rb @@ -16,22 +16,52 @@ def initialize @root = nil end - # Time Complexity: - # Space Complexity: + # Time Complexity: O(log n) + # Space Complexity: O(n) - call stack def add(key, value) - raise NotImplementedError + if @root.nil? + @root = TreeNode.new(key, value) + return true + end + + add_helper(key, value, @root) end - # Time Complexity: - # Space Complexity: - def find(key) - raise NotImplementedError + def add_helper(key, value, current) + return TreeNode.new(key, value) if current.nil? + + if key < current.key + current.left = add_helper(key, value, current.left) + else + current.right = add_helper(key, value, current.right) + end end - # Time Complexity: + # Time Complexity: O(log n) + # Space Complexity: O(n) - call stack + def find(key, current = @root) + return nil if current.nil? + return current.value if current.key == key + + if key < current.key + return find(key, current.left) + else + return find(key, current.right) + end + end + + # Time Complexity: # Space Complexity: - def inorder - raise NotImplementedError + def inorder(current = @root, answer = []) + + # Current + unless current.nil? + answer += inorder(current.left, answer) + return {key: current.key, value: current.value} + answer += inorder(current.right, answer) + end8 + + return answer end # Time Complexity: @@ -64,3 +94,11 @@ def to_s return "#{self.inorder}" end end + +# tree = Tree.new +# tree.add(5, "Peter") +# tree.add(3, "Paul") +# tree.add(1, "Mary") +# tree.add(10, "Karla") +# tree.add(15, "Ada") +# tree.add(25, "Kari") \ No newline at end of file From d09e5d604d74f57ee6a9b268cbe8f35e18a714bc Mon Sep 17 00:00:00 2001 From: Beatrice T Date: Sun, 4 Apr 2021 21:37:53 -0700 Subject: [PATCH 2/4] this is another commit message --- lib/tree.rb | 60 +++++++++++++++++++++++++++++++++-------------------- 1 file changed, 37 insertions(+), 23 deletions(-) diff --git a/lib/tree.rb b/lib/tree.rb index c64ba23..1821674 100644 --- a/lib/tree.rb +++ b/lib/tree.rb @@ -35,6 +35,8 @@ def add_helper(key, value, current) else current.right = add_helper(key, value, current.right) end + + return current end # Time Complexity: O(log n) @@ -50,30 +52,41 @@ def find(key, current = @root) end end - # Time Complexity: - # Space Complexity: + # Time Complexity: O(n) + # Space Complexity: O(n) def inorder(current = @root, answer = []) - # Current - unless current.nil? - answer += inorder(current.left, answer) - return {key: current.key, value: current.value} - answer += inorder(current.right, answer) - end8 + if current + inorder(current.left, answer) + answer.push({key: current.key, value: current.value}) + inorder(current.right, answer) + end return answer end - # Time Complexity: - # Space Complexity: - def preorder - raise NotImplementedError + # Time Complexity: O(n) + # Space Complexity: O(n) + def preorder(current = @root, answer = []) + if current + answer.push({key: current.key, value: current.value}) + inorder(current.left, answer) + inorder(current.right, answer) + end + + return answer end - # Time Complexity: - # Space Complexity: - def postorder - raise NotImplementedError + # Time Complexity: O(n) + # Space Complexity: O(n) + def postorder(current = @root, answer = []) + if current + inorder(current.left, answer) + inorder(current.right, answer) + answer.push({key: current.key, value: current.value}) + end + + return answer end # Time Complexity: @@ -95,10 +108,11 @@ def to_s end end -# tree = Tree.new -# tree.add(5, "Peter") -# tree.add(3, "Paul") -# tree.add(1, "Mary") -# tree.add(10, "Karla") -# tree.add(15, "Ada") -# tree.add(25, "Kari") \ No newline at end of file +tree = Tree.new +tree.add(5, "Peter") +tree.add(3, "Paul") +tree.add(1, "Mary") +tree.add(10, "Karla") +tree.add(15, "Ada") +tree.add(25, "Kari") +puts tree.preorder \ No newline at end of file From 22f6370cb008cfcdfd71ffd43f11b9d37b4ca46e Mon Sep 17 00:00:00 2001 From: Beatrice T Date: Tue, 13 Apr 2021 22:30:01 -0700 Subject: [PATCH 3/4] finished assignment --- lib/tree.rb | 20 ++++++++++++-------- test/tree_test.rb | 24 ++++++++++++------------ 2 files changed, 24 insertions(+), 20 deletions(-) diff --git a/lib/tree.rb b/lib/tree.rb index 1821674..6caca32 100644 --- a/lib/tree.rb +++ b/lib/tree.rb @@ -70,8 +70,8 @@ def inorder(current = @root, answer = []) def preorder(current = @root, answer = []) if current answer.push({key: current.key, value: current.value}) - inorder(current.left, answer) - inorder(current.right, answer) + preorder(current.left, answer) + preorder(current.right, answer) end return answer @@ -81,18 +81,22 @@ def preorder(current = @root, answer = []) # Space Complexity: O(n) def postorder(current = @root, answer = []) if current - inorder(current.left, answer) - inorder(current.right, answer) + postorder(current.left, answer) + postorder(current.right, answer) answer.push({key: current.key, value: current.value}) end return answer end - # Time Complexity: - # Space Complexity: - def height - raise NotImplementedError + # Time Complexity: O(n) + # Space Complexity: O(n) + def height(current = @root) + unless current + return 0 + end + + return 1 + [height(current.left), height(current.right)].max end # Optional Method diff --git a/test/tree_test.rb b/test/tree_test.rb index 60f5981..801f9ee 100644 --- a/test/tree_test.rb +++ b/test/tree_test.rb @@ -51,7 +51,7 @@ end it "will return the tree in preorder" do - expect(tree_with_nodes.preorder).must_equal [{:key=>5, :value=>"Peter"}, {:key=>3, :value=>"Paul"}, + expect(tree_with_nodes.preorder).must_equal [{:key=>5, :value=>"Peter"}, {:key=>3, :value=>"Paul"}, {:key=>1, :value=>"Mary"}, {:key=>10, :value=>"Karla"}, {:key=>15, :value=>"Ada"}, {:key=>25, :value=>"Kari"}] end @@ -91,7 +91,7 @@ it "will return 1 for a tree of height 1" do my_tree = Tree.new - my_tree.add(100) + my_tree.add(100, 100) expect(my_tree.height).must_equal 1 end @@ -102,11 +102,11 @@ it "will report the height for unbalanced trees" do my_tree = Tree.new - my_tree.add(100) - my_tree.add(110) - my_tree.add(120) - my_tree.add(130) - my_tree.add(140) + my_tree.add(100, 100) + my_tree.add(110, 110) + my_tree.add(120, 120) + my_tree.add(130, 130) + my_tree.add(140, 140) expect(my_tree.height).must_equal 5 @@ -114,11 +114,11 @@ my_tree = Tree.new - my_tree.add(100) - my_tree.add(90) - my_tree.add(80) - my_tree.add(70) - my_tree.add(60) + my_tree.add(100, 100) + my_tree.add(90, 90) + my_tree.add(80, 80) + my_tree.add(70, 70) + my_tree.add(60, 60) expect(my_tree.height).must_equal 5 end From a37ba73ca7bc1b03f0563822732716f6c0786d42 Mon Sep 17 00:00:00 2001 From: Beatrice T Date: Tue, 13 Apr 2021 22:39:30 -0700 Subject: [PATCH 4/4] remove cruft --- lib/tree.rb | 11 +---------- 1 file changed, 1 insertion(+), 10 deletions(-) diff --git a/lib/tree.rb b/lib/tree.rb index 6caca32..7cf01da 100644 --- a/lib/tree.rb +++ b/lib/tree.rb @@ -110,13 +110,4 @@ def bfs def to_s return "#{self.inorder}" end -end - -tree = Tree.new -tree.add(5, "Peter") -tree.add(3, "Paul") -tree.add(1, "Mary") -tree.add(10, "Karla") -tree.add(15, "Ada") -tree.add(25, "Kari") -puts tree.preorder \ No newline at end of file +end \ No newline at end of file