exercism fetch fsharp dominoes


Compute whether there exists a way to order a given set of dominoes in such a way that they form a correct domino chain (the dots on one half of a stone match the dots on the neighbouring half of an adjacent stone) and that dots on the halfs of the stones which don't have a neighbour (the first and last stone) match each other.

For example given the stones 21, 23 and 13 you should declare that there exists a possible chain (for example, 12, 23 and 31 is a possible chain).

For stones 12, 41 and 23 the resulting chain is not valid: 41 12 23's first and last numbers are not the same. 4 != 3

Some test cases may use duplicate stones in a chain solution, assume that multiple Domino sets are being used.

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.