initial commit

.gitignore

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+words_with_prefix.txt
+misspelled_words.txt

.ruby-version

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+2.4.1

README.md

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+## Ruby implementation of a trie that stores a dictionary
+* The dictionary can be used to spellcheck words and to suggest words that begin with a particular prefix
+* Associated [presentation](https://docs.google.com/presentation/d/1Zg0H-cHZjt-VvDdVxR1zdb1WsC3dfgkVVe_eXnP0uyM/edit?usp=sharing)
+
+### Dictionary format
+* each word is on a separate line
+* no empty lines
+* character set: uppercase and lowercase English alphabet, single apostrophe
+
+### Format of text to be spellchecked
+* Multiple words in a line
+* Has empty lines
+* character set: uppercase and lowercase English alphabet, single apostrophe, some punctuation marks
+
+### Usage
+* To spellcheck only: `./run`
+* To spellcheck and find words with a certain prefix: `./run $PREFIX` (eg: `./run super`)
+* Misspelled words are in `misspelled_words.txt`
+* Words that start with the given prefix are in `words_with_prefix.txt`
+* Total number of misspelled words and words that start with a given prefix are printed to the terminal
+* Time taken is benchmarked with ruby's `benchmark` gem
+
+### Notes
+* `SpellChecker.new('large.txt').spellcheck_lines('sonnets.txt')`
+  * If needed, swap out `large.txt` for another dictionary and/or `sonnets.txt` for another text file

dictionary.rb

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+class Dictionary
+  attr_reader :root
+
+  def initialize(file)
+    @root = Node.new
+    @cursor = @root
+    @counter = 0
+    add_words(file)
+  end
+
+  def add_words(file)
+    IO.foreach(file) do |word|
+      add_word(word.chomp)
+      @counter += 1
+    end
+    puts("Added #{@counter} words into the dictionary")
+  end
+
+  private
+  def add_word(word)
+    set_cursor_to_root
+
+    word.downcase.each_char do |char|
+      if @cursor.children.nil?
+        @cursor.children = Array.new(27)
+        @cursor.children[get_dict_index(char)] = Node.new
+      elsif @cursor.children[get_dict_index(char)].nil?
+        @cursor.children[get_dict_index(char)] = Node.new
+      end
+      move_cursor_to_next_node(char)
+    end
+
+    @cursor.is_word = true
+  end
+
+  def get_dict_index(char)
+    return 26 if char == "'"
+    char.ord - 97
+  end
+
+  def set_cursor_to_root
+    @cursor = @root
+  end
+
+  def move_cursor_to_next_node(char)
+    @cursor = @cursor.children[get_dict_index(char)]
+  end
+end