Heap (ruby heapsort)

Gem is using for making Heaps (binary only for now).

Installation

Add this line to your application's Gemfile:

gem 'ruby-heap'

And then execute:

$ bundle

Or install it yourself as:

$ gem install ruby-heap

Usage

Binary Heaps

Binary Heap with min root

While Heap initialize you can add any comparable object in it (not numbers only). Objects must have compare functions (>, >=, <, <=).

require 'Heap'

# Initialize
b_heap = Heap::BinaryHeap::MinHeap.new([2, 3, 1, -1])

# Return elements in Heap (read access only)
b_heap.elements     # [-1, 1, 3, 2]

# Return sorted array (heap-sort) without
# changing elements in heap
b_heap.sort         # [-1, 1, 2, 3]

# Count of elements in Heap
b_heap.count        # 4

# Return min element without removing from Heap
b_heap.extract_min  # -1

# Return min element and remove it from Heap
b_heap.extract_min! # -1
b_heap.count        # 3
b_heap.elements     # [1, 2, 3]

# Also you can add elements with "add" function
b_heap.add -1
b_heap.elements     # [-1, 1, 3, 2]
b_heap.add [0, 9, 200, -15, 6]
b_heap.elements     # [-15, -1, 3, 0, 1, 9, 200, 2, 6]
b_heap.sort         # [-15, -1, 0, 1, 2, 3, 6, 9, 200]

Same practice with max root

require 'Heap'

# Initialize
b_heap = Heap::BinaryHeap::MaxHeap.new([2, 3, 1, -1])

# Return elements in Heap (read access only)
b_heap.elements     # [3, 2, 1, -1]

# Return sorted array (heap-sort) without
# changing elements in heap
b_heap.sort         # [3, 2, 1, -1]

# Count of elements in Heap
b_heap.count        # 4

# Return min element without removing from Heap
b_heap.extract_max  # 3

# Return min element and remove it from Heap
b_heap.extract_max! # 3
b_heap.count        # 3
b_heap.elements     # [2, -1, 1]

# Also you can add elements with "add" function
b_heap.add -1
b_heap.elements     # [2, -1, 1, -1]
b_heap.add [0, 9, 200, -15, 6]
b_heap.elements     # [200, 6, 9, 0, -1, 1, 2, -15, -1]
b_heap.sort         # [200, 9, 6, 2, 1, 0, -1, -1, -15]

Heap merging

require 'Heap'

# Initialize heaps
min_heap = Heap::BinaryHeap::MinHeap.new [1, 2, 3]
max_heap = Heap::BinaryHeap::MaxHeap.new [9, -1, 4]

# Merge heaps
min_heap.add max_heap

min_heap.count    # 6
min_heap.sort     # [-1, 1, 2, 3, 4, 9]

Multiple Heaps

Multiple (d-ary) heaps have same methods as binary. But initialize differs:

require 'Heap'

# First param is "d" of heap
# Second param is optional and can contain first elements
min_heap = Heap::MultipleHeap::MinHeap.new(5, [10, 20, 30])
max_heap = Heap::MultipleHeap::MaxHeap.new(7)

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at Project page. This project is intended to be a safe, welcoming space for collaboration.

License

The gem is available as open source under the terms of the MIT License.