date_night

This was my first project at Turing. The task was to build a binary tree data structure from scratch with functions that allowed us to traverse the tree, add data, remove data, and provide information about the tree. The assignment can be found here: http://backend.turing.io/module1/projects/date_night

Setup

To download the project and run the full test suite was written for the project.

git clone https://github.com/Maxscores/date_night.git
cd date_night
ruby tests/tree_test.rb
ruby tests/node_test.rb

To interact with the project in terminal run (inside date_night directory)

irb
require './lib/tree.rb'
tree = Tree.new

Instance Methods

These instance methods can be called on the Tree object:

insert

The insert method adds a new node with the passed-in data. Each node is comprised of a score and a movie title. It returns the depth of the new node in the tree.

tree.insert(61, "Bill & Ted's Excellent Adventure")
# => 0
tree.insert(16, "Johnny English")
# => 1
tree.insert(92, "Sharknado 3")
# => 1
tree.insert(50, "Hannibal Buress: Animal Furnace")
# => 2

include?

Verify/reject the presence of a score in the tree:

tree.include?(16)
# => true
tree.include?(72)
# => false

depth_of

Reports the depth of the tree where a score appears. Return nil if the score does not exist:

tree.depth_of(92)
# => 1
tree.depth_of(50)
# => 2

max

Which movie has the highest score in the list? What is it's score?

tree.max
# => {"Sharknado 3"=>92}

min

Which movie has the lowest score in the list? What is it's score?

tree.min
# => {"Johnny English"=>16}

sort

Return an array of all the movies and scores in sorted ascending order. Return them as an array of hashes.

tree.sort
# => [{"Johnny English"=>16},
#   {"Hannibal Buress: Animal Furnace"=>50},
#   {"Bill & Ted's Excellent Adventure"=>61},
#  {"Sharknado 3"=>92}]

load

Assuming we have a file named movies.txt with one score/movie pair per line:

tree.load_file('./lib/movies.txt')
# => 100

health

Report on the health of the tree by summarizing the number of child nodes (nodes beneath each node) at a given depth. Where the return value is an Array with one nested array per node at that level. The nested array is:

[Score of the node, Total number of child nodes, Percentage of all the nodes that are this node or it's children]

tree.insert(98, "Animals United")
tree.insert(58, "Armageddon")
tree.insert(36, "Bill & Ted's Bogus Journey")
tree.insert(93, "Bill & Ted's Excellent Adventure")
tree.insert(86, "Charlie's Angels")
tree.insert(38, "Charlie's Country")
tree.insert(69, "Collateral Damage")
tree.health(0)
=> [[98, 7, 100]]
tree.health(1)
=> [[58, 6, 85]]
tree.health(2)
=> [[36, 2, 28], [93, 3, 42]]

When the percentages of two nodes at the same level are dramatically different, like 28 and 42 above, then we know that this tree is starting to become unbalanced.

leaves

A leaf is a node that has no left or right value. How many leaf nodes are on the tree?

tree.leaves
# => 2

height

What is the height (aka the maximum depth) of the tree?

tree.height
# => 3