Tag Archives: permutations

Linkback to the Secret Santa Problem

Tom left a comment to my post Calculate the number of secret Santa permutations in C#. He used that example to build a site in JavaScript explaining how the algorithm works. It’s a pretty cool little page. Drop by and … Continue reading

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Send secret Santa emails in C#

This example shows how you can automatically send secret Santa emails for a party. The example Pick a secret Santa assignment in C# shows how you can quickly make secret Santa assignments. The post Calculate the number of secret Santa … Continue reading

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Calculate the number of secret Santa permutations in C#

The example Pick a secret Santa assignment in C# picks a valid permutation of the people so no one is mapped to himself or herself. Such a permutation is called a derangement. See that example for details. The number of … Continue reading

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Pick a secret Santa assignment in C#

In a secret Santa party, you put everyone’s names in a hat and people draw from the hat. Each person becomes the secret Santa for the person he draws and gets that person a present for the party. To keep … Continue reading

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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 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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