jhamon

require 'sqlite3'
require 'singleton'

class QuestionsDatabase < SQLite3::Database
  include Singleton
  
  def initialize
    super "aafollowers.db"  # Our test db
    self.results_as_hash = true
    self.type_translation = true

jhamon

key_array = [1,2,3] # => [1, 2, 3]
value_array = [4,5,6] # => [4, 5, 6]
silly_hash = { key_array => value_array } # => {[1, 2, 3]=>[4, 5, 6]}
key_array.pop # => 3

# After mutating the key the hash is broken
silly_hash # => {[1, 2]=>[4, 5, 6]}
silly_hash[key_array] # => nil
silly_hash[[1,2]] # => nil

jhamon

# coding: utf-8
require 'colorize'

class King < Piece
  include SteppingPieces
 
  def move_dirs
   [[0, -1], [0, 1], [1, 0], [-1, 0], [-1, -1], [-1, 1], [1, -1], [1, 1]]
  end
 

jhamon

class King < Piece
  include SteppingPieces

  def move_dirs
   [[0, -1], [0, 1], [1, 0], [-1, 0], [-1, -1], [-1, 1], [1, -1], [1, 1]]
  end

  def mark
    return "♚".colorize(@color)
  end

jhamon

module SteppingPieces
  # Movement for stepping pieces, e.g. King, Knight

  def moves(board)
    # returns array of valid move positions for self (a Piece instance)

    # Add movement vectors to current position
    moves = self.move_dirs.map { |vec| new_position(@pos, vec)}

    # We only allow moves that fall on the board.

jhamon

class Piece
  attr_reader :color
  attr_accessor :pos

  def initialize(color, pos)
    @color = color  # :white or :black
    @pos = pos      # position = [x, y]
  end
  
  def dup

jhamon

class TreeNode
  # ...
 
  def dfs(target_value = nil,  &blk)
    # Depth-first search.  Returns TreeNode instance
    # with target value, or nil if not in tree.  
    # Optionally accepts a block and returns the 
    # first node encounted for which the block 
    # evaluates to true. This allows us to dfs
    # search using arbitrary criteria.

jhamon

class TreeNode
  # ...

  def dfs(target_value = nil,  &blk)
    # Depth-first search.  Returns TreeNode instance
    # with target value, or nil if not in tree.  
    # Optionally accepts a block and returns the 
    # first node encounted for which the block 
    # evaluates to true. This is useful when 
    # searching for nodes using attributes other

jhamon

class TreeNode
   # ... omitted.
  
  def dfs(target_value = nil, &blk)
  # A (broken) first attempt at depth-first search
  # with arbitrary search criteria defined by the 
  # block received. 
    return self if !blk.nil && blk.call(@value)
    return self if @value == target_value
 

jhamon

class TreeNode
  attr_accessor :parent, :children 
  attr_reader :value

  def initialize(value)
    @value = value
    @parent = nil
    @children = []
  end