Prime numbers have a good deal of practical applications (for example in cryptography) but let's face it, even if they would have none, they would still be the favorite toy of mathematicians . In Problem 7 of Project Euler , we are asked to find the 10001st element of the famous list, my approach was...

This is another classic problem at Project Euler that can be solved with the old trick of top down programming, like so: PrimeFactors(number).DefaultIfEmpty(number).Max(); It's a nice solution, supposing PrimeFactors() actually returns all prime factors of any given number. But before getting there,...

The second problem at Project Euler proposes: Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... Find the sum of all the even-valued terms in the sequence which do not exceed...

[ LINQ via C# series ] The is a very simple feature. From partial class to partial method Partial class is introduced by C# 2.0. With the partial keyword, the definition of one type is able to be divided into several files. For example, if creating a WinForm application project in VisualStudio, the MainForm...

[ LINQ via C# series ] Lambda expression is another powerful syntactic sugar making C# functional. In this post, “Lambda expression” simply means “C# Lambda expression”. The native concept of lambda expression will be introduced in the later lambda calculus posts. According to MSDN : A lambda expression...

[ LINQ via C# series ] Extension method is a fancy and powerful syntactic sugar in C# 3.0. Extension methods are very important when writing functional style C# code. Define an extension method for a class When we define an extension method for a type, this extension method must: be a static method be...

[ LINQ via C# series ] This feature provides a way to create an instance without declare the type: var mark = new { Name = "Mark" , Age = 18 }; Since the type name is unknown at this time when writing code, this is called a anonymous type. Compilation At compile time, the compiler will generate the following...

[ LINQ via C# series ] Take this Person type as an example: public class Person { public string Name { get ; set ; } public int Age { get ; set ; } } Object initializer In C# 2.0 we create an Person instance and initialize it like this: Person person = new Person (); person.Name = "Mark" ; person.Age...

[ LINQ via C# series ] As the fundamental of LINQ, This chapter will explain the new language features of C# 3.0, all of which are syntactic sugars. This part is about the automatic property. In C# 2.0 a property can be declared like this: public class Person { private string _name; public string Name...

[ LINQ via C# series ] This kind of code has been introduced again and again: var positive = from number in source where number > 0 orderby number descending select number.ToString( CultureInfo .InvariantCulture); This is called the query expression syntactical sugar, providing a T-SQL-like way to...