re = /^[A-Z]{2}[A-Z0-9]{17,19}$/im
str = 'SI56020170014356205
LV80BANK0000435195001'
# 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