Which financial books would your focus on? C Sharp or pure C or C Plus Plus
This is one of those important decisions you come across. As the C# book explains, this languages makes you more productive with a 20% slower performance vs C or C++. Let me know what you think..

http://quantlabs.net/blog/2014/01/whoa-a-decent-looking-book-dotnet-csharp-for-financial-market-book-is-out-there/

http://quantlabs.net/blog/2014/01/yet-another-book-to-consider-the-encyclopedia-of-trading-strategies-with-coding-samples-in-c/