Calculate the day of the week for any date in your head https://news.ycombinator.com/item?id=21926097 … 9

Calculate the day of the week for any date in your head https://news.ycombinator.com/item?id=21926097 … 9

Calculate the day of the week for any date in your head https://news.ycombinator.com/item?id=21926097 … 9 via https://twitter.com/NewCapitalLLC_