The unpac monorepo manager self-hosting as a monorepo using unpac
fixed bug in Eulerian.path
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-10
+8
-6
src/eulerian.ml
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-6
src/eulerian.ml
···
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| _, 0 -> rev xy :: list_of (eulerian_cycle out x)
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| 0, _ -> xy :: list_of (eulerian_cycle out y)
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| _ ->
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(* a bit of a pity to use list concatenation here,
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but this does not change the complexity *)
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list_of (eulerian_cycle out x) @
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xy :: list_of (eulerian_cycle out y)
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let py = eulerian_cycle out y in
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(* caveat: the cycle from y may exhaust edges from x *)
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if out_degree out x = 0 then xy :: list_of py
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else list_of (eulerian_cycle out x) @ xy :: list_of py
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(* a bit of a pity to use list concatenation here,
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but this does not change the complexity *)
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) else (
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(* no edge x--y => add one, build a cycle, then remove it *)
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let dummy = E.label (snd (any (H.find out x))) in
···
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let directed _g =
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invalid_arg "Eulerian.path (directed graphs not yet supported)"
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let path g =
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if is_directed then directed g else undirected g
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let path =
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if is_directed then directed else undirected
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let cycle g =
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let p, c = path g in
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-4
tests/test_eulerian.ml
+8
-4
tests/test_eulerian.ml
···
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assert (List.length p = (n+1)*(2*n+1))
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done
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(* let () =
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* let g, _ = Classic.grid ~n:2 ~m:3 in
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* assert (exists_path g);
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* assert (not (exists_cycle g)) *)
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let () =
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(* +---x---+ tricky one, as the edge x-y
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| | | connects two vertices on a cycle
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+---y---+ *)
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let g, _ = Classic.grid ~n:2 ~m:3 in
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let p, c = Eulerian.path g in
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assert (not c);
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assert (List.length p = 7)
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