Tag Archives: combinations

New Book: The Modern C# Challenge

Posted on October 29, 2018 by RodStephens

My latest book, The Modern C# Challenge, is now available. It’s a collection of 100 programming challenges that let you test your ability in a wide variety of programming topics, many of which are not usually covered in traditional programming … Continue reading →

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Generate words of a given length in C#

Posted on August 5, 2016 by Rod Stephens

The example Generate three-letter words in C# uses three nested for loops to generate words that contain three letters. This example uses the following code to generate words of any given length. // Generate words with num_letters letters. private List … Continue reading →

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Generate three-letter words in C#

Posted on August 5, 2016 by Rod Stephens

This example uses the following very simple code to generate three-letter words using the letters a through z. // Make the items. private void Form1_Load(object sender, EventArgs e) { List<string> values = new List<string>(); for (char ch1 = ‘a’; ch1 … Continue reading →

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Select N random items from an array in C#

Posted on January 12, 2015 by Rod Stephens

This example builds a generic extension method that lets you easily select N random objects from an array. For example, it lets you select 5 items from an array holding 10 names. Picking one random item from an array is … Continue reading →

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Generate all selections of K items from a set of N items in C#

Posted on August 10, 2014 by Rod Stephens

This example is somewhat similar to Generate all of the permutations of a set of objects in C#. The basic idea is to use a recursive method to assign the next item to the combination. The first call to the … Continue reading →

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Generate all of the permutations of a set of objects in C#

Posted on August 10, 2014 by Rod Stephens

The basic idea is to use a recursive method to assign the next item in a permutation. The first call to the method assigns the permutation’s first item, the next call assigns the second item, and so forth. To assign … Continue reading →

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