IMO, doing the exercises in programming books is (almost) a complete waste of time, not to mention extremely boring.
You're better off testing what you learned in real programs instead of artificial examples without practical relevance.
I agree with Athar, I personally haven't tried any of the exercises nor have I bought the answer book.
Just code your on programs using the thing's you have learnt. This way you are better equipped to design any program from scratch.
doing the exercises in programming books is (almost) a complete waste of time
It all depends on the book, a good book will have worthwhile exercises. If the book just asks you to write pointless small programs, they are probable not worthwhile other than to drive home the syntax of a given construct. If they ask things like:
Which is the most appropriate, a vector, a deque, or a list for the following program tasks? Explain the rationale for your choice. If there is no reason to prefer one or another container explain why not?...
then it is worthwhile, as it make you think about what you have just read and maybe in the future you don't just opt for a vector.