[2023][ruby][7.x] refactoring

2023/ruby/day_07.rb

@@ -1,46 +1,31 @@
-module PartOne
-  CARD_ORDER = ((?2..?9).to_a + %w[ T J Q K A ]).each.with_index.to_h
-
-  Card = Data.define(:rank) do
-    def <=>(other)
-      CARD_ORDER.fetch(self.rank) <=> CARD_ORDER.fetch(other.rank)
-    end
-  end
+HAND_STRENGTH = [
+  [5],             # five of a kind
+  [1, 4],          # four of a kind
+  [2, 3],          # full house
+  [1, 1, 3],       # three of a kind
+  [1, 2, 2],       # two pair
+  [1, 1, 1, 2],    # one pair
+  [1, 1, 1, 1, 1], # high card
+].reverse.each.with_index.to_h { [_1, _2] }
 
-  Hand = Data.define(:cards) do
-    def type
-      tally = self.cards.tally
-      case tally.values.sort
-      when [5]             then 5   # five of a kind
-      when [1, 4]          then 4   # four of a kind
-      when [2, 3]          then 3.5 # full house
-      when [1, 1, 3]       then 3   # three of a kind
-      when [1, 2, 2]       then 2.5 # two pair
-      when [1, 1, 1, 2]    then 2   # one pair
-      when [1, 1, 1, 1, 1] then 1   # high card
-      else fail "couldn't calculate type: #{self.inspect}"
-      end
-    end
+module PartOne
+  CARD_STRENGTH = ((?2..?9).to_a + %w[ T J Q K A ]).each.with_index.to_h
 
-    def <=>(other)
-      v = self.type <=> other.type
-      v.zero? ? self.cards <=> other.cards : v
-    end
+  def self.strength(cards)
+    tally = cards.tally
+    strengths = [
+      HAND_STRENGTH.fetch(tally.values.sort),
+      *cards.map { CARD_STRENGTH.fetch(_1) },
+    ]
+    strengths.map { (?a.ord + _1).chr }.join
   end
 end
 
 module PartTwo
-  CARD_ORDER = ([?J] + (?2..?9).to_a + %w[ T Q K A ]).each.with_index.to_h
+  CARD_STRENGTH = ([?J] + (?2..?9).to_a + %w[ T Q K A ]).each.with_index.to_h
 
-  Card = Data.define(:rank) do
-    def <=>(other)
-      CARD_ORDER.fetch(self.rank) <=> CARD_ORDER.fetch(other.rank)
-    end
-  end
-
-  Hand = Data.define(:cards) do
-    def type
-      tally = self.cards.map(&:rank).tally
+  def self.strength(cards)
+    tally = cards.tally
     jokers = tally.delete(?J) || 0
     counts = tally.values.sort
     if counts.empty?
@@ -48,30 +33,18 @@ module PartTwo
     else
       counts[-1] += jokers
     end
-      case counts
-      when [5]             then 5   # five of a kind
-      when [1, 4]          then 4   # four of a kind
-      when [2, 3]          then 3.5 # full house
-      when [1, 1, 3]       then 3   # three of a kind
-      when [1, 2, 2]       then 2.5 # two pair
-      when [1, 1, 1, 2]    then 2   # one pair
-      when [1, 1, 1, 1, 1] then 1   # high card
-      else fail "couldn't calculate type: #{self.inspect}"
-      end
-    end
-
-    def <=>(other)
-      v = self.type <=> other.type
-      v.zero? ? self.cards <=> other.cards : v
-    end
+    strengths = [
+      HAND_STRENGTH.fetch(counts),
+      *cards.map { CARD_STRENGTH.fetch(_1) },
+    ]
+    strengths.map { (?a.ord + _1).chr }.join
   end
 end
 
-hands = ARGF.read.scan(/(\w+)\s+(\d+)/).to_h {|hand, bid|
-  [PartTwo::Hand.new(hand.chars.map { PartTwo::Card.new(_1) }), bid.to_i]
-}
+hands = ARGF.read.scan(/(\w+)\s+(\d+)/).to_h { [_1.chars, _2.to_i ] }
 
 p hands
-  .sort_by(&:first)
+  # .sort_by {|(hand,_)| PartOne::strength(hand) }
+  .sort_by {|(hand,_)| PartTwo::strength(hand) }
   .map.with_index {|(_,bid),i| bid * (i+1) }
   .sum