[2023][ruby][11.2]

2023/ruby/day_11.rb

@@ -1,13 +1,37 @@
-image = ARGF.read
-image.gsub!(/^(\.+)$/m, "\\1\n\\1")
-image = image.split("\n").map(&:chars).transpose.map(&:join).join("\n")
-image.gsub!(/^(\.+)$/m, "\\1\n\\1")
-image = image.split("\n").map(&:chars)
-
-galaxies = image.flat_map.with_index {|row, y|
-  row.filter_map.with_index {|elem, x| elem == ?# ? [y,x] : nil }
-}
+image = ARGF.readlines(chomp: true).map(&:chars)
+empty_rows = image.filter_map.with_index {|row,y| row.all? { _1 == ?. } ? y : nil }
+empty_cols = image.transpose.filter_map.with_index {|col,x| col.all? { _1 == ?. } ? x : nil }
+
+galaxies = []
+y = x = 0
+image.each.with_index do |row, yy|
+  x = 0
+  row.each.with_index do |elem, xx|
+    galaxies << [y,x] if elem == ?#
+    x += 1
+    x += 999_999 if empty_cols.include?(xx)
+  end
+
+  y += 1
+  y += 999_999 if empty_rows.include?(yy)
+end
 
 p galaxies.combination(2).sum {|a, b|
   a.zip(b).sum { (_1 - _2).abs }
 }
+
+# original part one
+
+# image = ARGF.read
+# image.gsub!(/^(\.+)$/m, "\\1\n\\1")
+# image = image.split("\n").map(&:chars).transpose.map(&:join).join("\n")
+# image.gsub!(/^(\.+)$/m, "\\1\n\\1")
+# image = image.split("\n").map(&:chars)
+
+# galaxies = image.flat_map.with_index {|row, y|
+#   row.filter_map.with_index {|elem, x| elem == ?# ? [y,x] : nil }
+# }
+
+# p galaxies.combination(2).sum {|a, b|
+#   a.zip(b).sum { (_1 - _2).abs }
+# }