Step by Step solution about How to resolve the algorithm Set, the card game step by step in the Ruby programming language

The provided code is a Ruby program that deals a hand of cards and checks for sets of three cards that share a common attribute (number, shading, color, or symbol) while having different values for the other three attributes. A detailed explanation of the code is as follows:

1. Constants and Data Structures:

   • ATTRIBUTES is an array of attribute names ([:number, :shading, :colour, :symbol]) used to represent the attributes of a card.
   • Card is a Struct that takes the attribute names as arguments and defines a to_s method to represent a card as a string by joining its attribute values with a space.
   • combis is a list of combinations of attributes using %i[] for symbols, resulting in a list of tuples ([:one, :solid, :red, :diamond], [:one, :solid, :red, :oval], and so on).
   • PACK is an array of Card objects created by mapping the combis list to Card.new to construct all possible cards.

2. Helper Method:

   • set? is a helper method that takes a trio of cards and checks if they are a set by verifying that each attribute has unique values among the three cards.

3. Main Logic:

   • The code deals hands of different sizes (4, 8, and 12) by sampling from PACK and prints the dealt hand.
   • It then finds sets within the hand using combination(3) to generate all possible combinations of three cards and filters them using the set? method.
   • The number of sets found is printed, and each set is printed on a separate line.

The program demonstrates a concise and efficient way to deal cards, check for sets, and display the results.

ATTRIBUTES = [:number, :shading, :colour, :symbol]
Card    = Struct.new(*ATTRIBUTES){ def to_s = values.join(" ") }
combis  = %i[one two three].product(%i[solid striped open], %i[red green purple], %i[diamond oval squiggle])
PACK = combis.map{|combi| Card.new(*combi) }

def set?(trio) = ATTRIBUTES.none?{|attr| trio.map(&attr).uniq.size == 2 }

[4, 8, 12].each do |hand_size|
  puts "#{"_"*40}\n\nCards dealt: #{hand_size}"
  puts hand = PACK.sample(hand_size)
  sets = hand.combination(3).select{|h| set? h }
  puts "\n#{sets.size} sets found"
  sets.each{|set| puts set, ""}
end