15 lines
415 B
Text
15 lines
415 B
Text
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;; use the obvious methos
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(lib 'list) ; for (permutations) function
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;; input
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(define perms '
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(ABCD CABD ACDB DACB BCDA ACBD ADCB CDAB DABC BCAD CADB CDBA CBAD ABDC ADBC BDCA DCBA BACD BADC BDAC CBDA DBCA DCAB))
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;; generate all permutations
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(define all-perms (map list->string (permutations '(A B C D))))
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→ all-perms
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;; {set} substraction
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(set-substract (make-set all-perms) (make-set perms))
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→ { DBAC }
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