The thing that has always struck me about K&R is that it contains no fluff. You get so much information for each paragraph, that you often have to re-read them to get all the information contained therein. Probably the programming book I've used the most.
In contrast, the C++ programming language is a mouthful, and ended up being just another pretty book on my bookshelf.
Stroustrop is, or at least in its later editions became, a pretty indespensable C++ book. Most of the topics in C++ are best addressed by it. Unfortunately, C++ is a nightmare of a language, so there are many, many topics, and you don't read it cover-to-cover any more than a cook would read New Pro Chef or McGee cover-to-cover.
I have read neither K&R nor the C++ book cover-to-cover, but the C++ book is standing practically unused on my bookshelf, while my K&R is noticeably worn.
In contrast, the C++ programming language is a mouthful, and ended up being just another pretty book on my bookshelf.