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I have been trying to figure out how to generate permutations of the elements in a list in user RPL w/ my 48gii. I know I can write a brute force generator but it seems there should be some elegant way to do this with P2C and/or C2P and perhaps DOLIST or DOSUB but I'm getting nowhere understanding the cycle notation stuff.

Am I whistling in the wind here or is there a way?

My simple test case is to generate all the permutations of the elements in the list {1 2 3 4}.

Thanks,
Norm

@ 119.5 bytes, (48G) #48407d

\<<

  { {} } OVER SIZE 1 SWAP

  FOR j

    OVER j GET ADD

    1

    \<<

      DUP +

      1 j

      START

        TAIL DUP 1 j SUB SWAP

      NEXT

      DROP

    \>>

    DOSUBS

  NEXT

  SWAP DROP

\>>

Brilliant Werner!

I'll be studying this for a while.