Yes, you've guessed correctly - the answer is "42". In this article you will find 42 recommendations about coding in C++ that can help a programmer avoid a lot of errors, save time and effort. The author is Andrey Karpov - technical director of "Program Verification Systems", a team of developers, working on PVS-Studio static code analyzer. Having checked a large number of open source projects, we have seen a large variety of ways to shoot yourself in the foot; there is definitely much to share with the readers. Every recommendation is given with a practical example, which proves the currentness of this question. These tips are intended for C/C++ programmers, but usually they are universal, and may be of interest for developers using other languages.
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I hope you enjoyed this collection of tips. Of course, it is impossible to write about all the ways to write a program incorrectly, and there is probably no point in doing this. My aim was to warn a programmer, and to develop a sense of danger. Perhaps, next time when a programmer encounters something odd, he will remember my tips and won't haste. Sometimes several minutes of studying the documentation or writing simple/clear code can help to avoid a hidden error that would make the life of your colleagues and users miserable for several years.