Compression challenge (https://corgicorporation.medium.com/if-software-engineering-is-in-demand-why-is-it-so-hard-to-get-a-software-engineering-job-c043a964e463)

string_compressor.rb

def generate_code(number)
  charset = Array('A'..'Z') + Array('a'..'z')
  Array.new(number) { charset.sample }.join
end

org_string = ARGV.first || generate_code(100)
solution = ''
string = org_string.split('')
string.each_with_index do |letter, index|
  next if index.zero?

  if letter == string[index - 1][-1]
    string[index] += string[index - 1]
  else
    solution += "#{string[index - 1][-1]}#{string[index - 1].size if string[index - 1].size > 1}"
  end
end
puts "Original:\t#{org_string}"
print "Compressed:\t"
solution += "#{string[-1]}#{string[-1].size if string[-1].size > 1}"
puts solution

string_compressor2.rb

def generate_code(number)
  charset = Array('A'..'Z') + Array('a'..'z')
  Array.new(number) { charset.sample }.join
end


string = ARGV.first || generate_code(100)
solution = {}

string.split('').each do |letter|
  solution[letter] = if solution.keys.include? letter
                       solution[letter] + 1
                     else
                       1
                     end
end

puts "Original:\t#{string}"
puts "Compressed:\t#{solution.sort_by { |letter, _| letter }.to_a.flatten.map(&:to_s).join}"