add day 08: Space Image Format

Author: petertseng

08_space_image_format.rb

@@ -0,0 +1,16 @@
+verbose = ARGV.delete('-v')
+
+width = 25
+layer = width * 6
+
+input = ARGF.read.chomp
+
+layers = input.each_char.each_slice(layer).to_a
+
+min_layer = layers.min_by { |x| x.count(?0) }
+p min_layer.tally if verbose
+puts min_layer.count(?1) * min_layer.count(?2)
+
+pixels = layers.transpose.map { |pixel| pixel.find { |layer| layer != ?2 } }
+disp = {?1 => ?#, ?0 => ' '}.freeze
+pixels.each_slice(width) { |row| puts row.map { |pixel| disp.fetch(pixel) }.join }