Talk:Knuth's Algorithm X: Difference between revisions

Revision as of 23:09, 18 January 2013

Revision as of 13:18, 12 December 2013

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:I think the algorithm is incorrect as in missing the following rule:

: 2. If there is a column ''c'' without any 1s, terminate unsuccessfully, otherwise choose a column ''c'' ([[deterministic algorithm|deterministically]]). -- [[Special:Contributions/139.18.249.154|139.18.249.154]] ([[User talk:139.18.249.154|talk]]) 13:15, 18 October 2011 (UTC)

'''I totally agree''' — the rule should be explicitly reported in the scheme box, as the 2nd condition on which the algoritm terminates

(this time unsuccessfully). Perhaps, the best place to put it would be right after point 1 (i.e., after the successful the termination condition). While it is obvious why the algorithm should stop unsuccessfully on any matrix having an all-zero column (no complete coverage is possible in this case, since the set element represented by such column belongs to no subset), the way in which the (nice) example is worked out makes the unsuccessful termination of '''Level 1: Select Row A''' unnecessarily obscure.[[User:Banquo71|Banquo71]] ([[User talk:Banquo71|talk]]) 13:18, 12 December 2013 (UTC)

==Quotation without attribution==