What is Reddit's opinion of Challenging Problems in Geometry (Dover Books on Mathematics)?

From 3.5 billion Reddit comments

You could try this book.

http://www.amazon.com/dp/0486691543/ref=wl_it_dp_o_pC_S_img?_encoding=UTF8&colid=2FG5V4E5XPKQG&coliid=IN08Z4T2PWM88

If you have previous experience in geometry then Challenging Problems in Geometry by Posamentier and Salkind is a very helpful resource. If you're just beginning then The Art of Problem Solving's Introduction to Geometry is a nice book to learn from. The former is strictly a problem book that doesn't have a lot of theory attached to it. On the other hand, the latter book has a lot of introductory theory that is really helpful when first starting out with geometry.