Math::Combinatorics will not do the trick: it will give you all the permutations of an array or list, but cannot do nPk where n < k. Use Algorithm::Permute for that.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re^2: Need a faster way to find matches by CountZero
in thread Need a faster way to find matches by remzak

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