Tuesday, November 23, 2004

Factorials, Combinations and Permutations

A while back on the TDAG list Bob Murdoch was trying to figure out Combinations in Delphi. I wrote this code for him and anyone else who is interested. Combination needs Factorial, and I decided to through Permutation (which also needs Factorial) in for good measure. I added an optimization in on Combination that requires an additional parameter (AStop) on Factorial. (Thanks to Brian Mayland for pointing out a bug in my optimization.) If you are calling factorial directly then just leave AStop as 0 [Zero]. If you wanted to you could have an overloaded version of Factorial instead of using a default parameter.

The code is available under MPL or LGPL.

[.html] [.pas] [.zip]

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