dragonwasrobot / learn-prolog-now-exercises

My solutions to the exercises and practical sessions of the book 'Learn Prolog Now!' by Patrick Blackburn, Johan Bos, and Kristina Striegnitz.
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Second strategy for subset/2 predicate #46

Closed hailangvn closed 5 years ago

hailangvn commented 5 years ago

Hi dragonwasrobot, I have just read from a book of a Japanese Zen master that Western usually think about "Adding" to solve a problem, while Japanese usually think about "Removing" for the same problem. And I found this is an example. So besides the strategy to build list of subset in advance, I propose the strategy to remove element from two sets.

Please consider this PR. Thank you for sharing all the solutions.