alexwebgr

    PARENS = {
      "(" => ")",
      "{" => "}",
      "[" => "]"
    }
    OPENING_PARENS = PARENS.keys
    CLOSING_PARENS = PARENS.values
    def valid_parentheses(string)
      stack  = []
      string.each_char do |ch|

alexwebgr

# Completely remove any previous config
sudo apt remove --purge mysql*
sudo apt autoremove
sudo find / -iname mysql

# install the server
sudo apt update
sudo apt install mysql-server
# run the wizard
sudo mysql_secure_installation

alexwebgr

str = "aabbbaa"
count = Hash.new(0)
str.each_char { |c| count[c] += 1 }
puts count

alexwebgr

# generate and edit env-specific encrypted credentials 
EDITOR=nano bin/rails encrypted:edit config/development.yml.enc --key config/development.key

# override credentials in application.rb
def credentials
  encrypted(
    "config/#{Rails.env.downcase}.yml.enc",
    key_path: "config/#{Rails.env.downcase}.key"
  )
end