Hello there.
As everyone knows, real life problems when it comes to programming are numerous and often unexpected. Sometimes, those problems even are hard to solve, and without being trained to recognize them, you can quickly get stuck. I like challenge, because the more you get confronted to a recurrent situation, the less time you need to come up with an efficient answer -in time complexity, for instance- when you encounter a similar issue.
This leads to my question :
Does anybody know a good book, or any kind of support, that remains language independent enough, providing problems that tends to be hard at some point, probably crescent difficulty, to practice coding. I mean, these problems that are addictive and interesting, and you feel a real achievement when you solve them. Something like, if you don't find a trick to get your algorithm time-linear, while there also is an expensive brute-force version, it will lead you to failure.
Thanks already for your suggestions.