Die C++-Challenge: Echte Probleme lösen und zum C++-Experten werden - 100 Aufgaben und ausprogrammierte Lösungen

by Marius Bancila

Test your C++ programming skills by solving real-world programming problems covered in the book C++ is one of the most widely-used programming languages and has applications in a variety of fields, such as gaming, GUI programming, and operating systems, to name a few. Through the years, C++ has evolved into (and remains) one of the top choices for software developers worldwide. This book will show you some notable C++ features and how to implement them to meet your application needs. Each problem is unique and doesn't just test your knowledge of the language; it tests your ability to think out of the box and come up with the best solutions. With varying levels of difficulty, you'll be faced with a wide variety of challenges. And in case you're stumped, you don't have to we've got the best solutions to the problems in the book. So are you up for the challenge? This book will appeal to C++ developers of all levels. There's a challenge inside for everyone.

Genres: Programming, Computer Science

Paperback

Published November 12, 2018

Reviews

[Aoshi · Rating 3 out of 5]

Good idea, lackluster execution.

As of writing this, I've done around 85 of the 100 problems, and the word that comes to mind to best describe this would be "unpolished". The problems themselves could often do with more exposition (I can look up the definition of an Armstrong number, for instance, but would it be so hard to add it to the text?). There were times when I interpreted what the output of the problem should be in a different way (when I see the word histogram, I'm expecting to produce an actual histogram), or creating iterators instead of just copying things to a container. This isn't a huge problem however, at worst, it makes some of the problems slightly more difficult.

It'd be nice if they provided some canned/test data on their repo to use in tests or for basic setup for some of the questions as well.

I have some issues with the solutions; partial minor spoilers ahead I suppose.



These are just some notes I've jotted down regarding their solutions:

- Distinct lack of usage of constexpr for most of the math section problems, almost every problem has at least one function that can be constexpr, a number of entire solutions can be constexpr. Also uses long long where they should just be using uint64_t, and sometimes has manual definitions for copy constructor / copy assignment where they are entirely unnecessary.

- Timing a callable (problem 39) is kind of lazy I feel - this should actually return the result of the callable as well if there is one. This is something that shows off C++17 as well, as it is much, much easier to deal with the is_void / is_pointer / is_lvalue_reference / is_const / is_value combinations using if constexpr compared to the specializations required in C++11/14. Perhaps this is just my opinion though.

- The iterator implementation for circular buffer (problem 46) are wrong. It declares random_access_iterator_tag but doesn't implement operator+= or operator-=. Only implements const_iterators. Holds a constant reference to the container (as opposed to a pointer or reference_wrapper) which means it is not default constructable or copyable, which iterators should be. operator-> should return const_pointer, not const_reference. Their own test code doesn't even test the iterators at all.

- The swap function for double buffer (problem 47) should take a reference; this shouldn't even compile as written as it's trying to copy an object that contains a mutex. In fact, the swap implementation is even more broken, as it should be taking locks (via std::lock(mt, other.mt)) on both buffers before swapping their members. Finally, it should probably have a separate lock for reads and writes.

- Implementation for zip (problem 55) is just stuffing pairs into a container; I was expecting an iterator-based implementation (although getting operator-> correct for this is tricky).

- Just about every solution in the concurrency section uses std::forward(f) within a loop, which is probably going to do bad things(TM) with rvalue-reference stateful callables.



All in all, I think this is a good idea, I just wish they'd put more effort into it.

[Dendi · Rating 5 out of 5]

I think the hands-on examples are amazing to get you up to speed to C++17/2a. Recommended to anyone who has C++11 expertise to delve into C++17/2a.

[Brian Riordan · Rating 4 out of 5]

I good set of problems to learn C++ and libraries well. You could use these problems to learn any language.