fixed cycle detection in exists_directed_cycle#255
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kunwuz merged 1 commit intopy-why:mainfrom Mar 27, 2026
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with c in V continue, this will never be able to detect cycles where node_from == node_to, since node_from is always in V, thereby continuing when c == node_to (since c in V takes precedent) Signed-off-by: Max Hahn <40292613+maxhahn@users.noreply.github.com>
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Thank you so much for your fix! |
kunwuz
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Mar 27, 2026
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The cycle detection is broken, since the case
c==node_tocan never be reached sincec in Vcomes before, which is true whennode_from==node_toas is the case with the cycle check.Please let me know if I am mistaken, but a simple graph A->B->C and C->A was determined to have no cycle without this fix.