Heap (ruby heapsort)

Русская версия README

Gem is used to create Heap structs and sort via Heapsort algorithm.

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 max element without removing from Heap
b_heap.extract_max  # 3

# Return max 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)

Contributing

Bug reports and pull requests are welcome on GitHub at Project page.

License

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