10 lines
488 B
Text
10 lines
488 B
Text
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#import std
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permutations =
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~&itB^?a( # are both the input argument list and its tail non-empty?
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@ahPfatPRD *= refer ^C( # yes, recursively generate all permutations of the tail, and for each one
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~&a, # insert the head at the first position
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~&ar&& ~&arh2falrtPXPRD), # if the rest is non-empty, recursively insert at all subsequent positions
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~&aNC) # no, return the singleton list of the argument
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