woooo

gistfile1.rb

class WFString
  REFLECTION = { "{" => "}", "(" => ")", "[" => "]"}

  def self.check(string)
    first_in = []
    surround_string = string.gsub(/[^\[\]\{\}\(\)]/, "")
    return false if surround_string.length % 2 != 0
    surround_string.chars.each do |symbol|
      if REFLECTION[symbol]
        first_in << symbol
      else
        return false unless REFLECTION[first_in.last] == symbol
        first_in.pop
      end
    end
    true
  end
end