aoc-2022/2.rb

input = File.read("2.input").split("\n").map {|line| line.split(" ")}

@shape_score = {"A" => 1, "B" => 2, "C" => 3}
@result_score = {"X" => 0, "Y" => 3, "Z" => 6}

@win_map = {"A" => "C", "B" => "A", "C" => "B"}
@lose_map = @win_map.invert

def result_to_shape(opponent, result)
  if result == "X" then
    return @win_map[opponent]
  elsif result == "Y" then
    return opponent
  else
    return @lose_map[opponent]
  end
end

def shapes_to_result(me, opponent)
  if me == opponent then
    return "Y"
  elsif @win_map[me] == opponent then
    return "Z"
  else
    return "X"
  end
end

def task1(opponent, me)
  shape_map = {"X" => "A", "Y" => "B", "Z" => "C"}

  me = shape_map[me]

  return @result_score[shapes_to_result(me, opponent)] + @shape_score[me]
end

def task2(opponent, result)
  return @result_score[result] + @shape_score[result_to_shape(opponent, result)]
end

puts input.map {|line| task1(line[0], line[1])}.sum()
puts input.map {|line| task2(line[0], line[1])}.sum()