I am an Digital Marketing Consultant. Making creative digital strategists to produce innovative and unique, data-driven campaigns about industry trends.
I am having 8 years of experience in Digital Marketing. Certified Google Adwords, Analytics, Google Tag Manager, Bing Ads.
I recommend to use sub directory if you want to take the SEO advantage.
In sub domain, authority & link juice will not pass and Google treat every sub domain as a separate entity.
I hope this helps.