Initial data commit

Task/Non-transitive-dice/Factor/non-transitive-dice.factor

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+USING: grouping io kernel math math.combinatorics math.ranges
+prettyprint sequences ;
+
+: possible-dice ( n -- seq )
+    [ [1,b] ] [ selections ] bi [ [ <= ] monotonic? ] filter ;
+
+: cmp ( seq seq -- n ) [ - sgn ] cartesian-map concat sum ;
+
+: non-transitive? ( seq -- ? )
+   [ 2 clump [ first2 cmp neg? ] all? ]
+   [ [ last ] [ first ] bi cmp neg? and ] bi ;
+
+: find-non-transitive ( #sides #dice -- seq )
+    [ possible-dice ] [ <k-permutations> ] bi*
+    [ non-transitive? ] filter ;
+
+! Task
+"Number of eligible 4-sided dice: " write
+4 possible-dice length . nl
+
+"All ordered lists of 3 non-transitive dice with 4 sides:" print
+4 3 find-non-transitive . nl
+
+"All ordered lists of 4 non-transitive dice with 4 sides:" print
+4 4 find-non-transitive .