secret-santa-matcher

An attempt at providing a solution for iodigital-com/SecretSanta#510

This is the C# implementation of https://github.com/jorimvanhove/secret-santa-codechallenge-510

Functional requirements

Write an algorithm that assigns every participant to another participant

Given participants A, B, C, D, E.
Could result in A -> B -> C -> D -> E -> A (randomization is required)
Multiple loops like A -> B -> A + C -> D -> E -> C are allowed
A -> A is not allowed

Must work with an odd number of participants

Participants can have (multiple) excludes

Eg this must work:

A: exclude C, D, E
B: exclude A, D, E
C: exclude A, B, E
D: exclude A, B, C
E: exclude B, C, D

In this case the only valid list is A -> B -> C -> D -> E -> A

The solution must error-handle a situation that can't be resolved.

Eg with participants A, B, C:

A: exclude C
B: exclude C
C: -

This would result in A -> B -> A and a C that can't be assigned.

Must run in an acceptable time with > 200 participants.