re = /([A-Z]{2}\d\s([A-Z]+\s)+)|([A-Z]{3}\s([A-Z]+\s)+)/mi
str = 'ABC D A F DE3 D CD A
AB3 D T B
AE1 A D BE1 A D C
AE1 A E F
ABC D A F DE3 D CD A
'
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html