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rant.gulbrandsen.priv.no
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I tagged this rant because it is. I hate how “advent calendar” has come to mean “series of promotional postings” so here’s an actual advent calendar, the kind to appeal to our sort. And a neat hack it is, too. The postscript code is good or awful, your opinion may vary.

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The link on the article linking to the four-fours problem seems to be broken.

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Sigh, and that after less than ten years. I hate link rot. OK, updated to point to the Wikipedia page. Which is worth a rant of its own, but I’m going to try to write code.

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Many thanks.

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I wonder if anyone can improve on the arrangement for 18. They have:

(4^2 + 4) - (4 / sqrt(4))

The game is generally to make the target number using only four fours, brackets and arithmetic operators.

They also use 44 a couple of times and would like to do something else. e.g. 13 is

4! − 44 / 4

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Ah, 4 / sqrt(4) == sqrt(4), so we can save a 4 there giving `4 * 4 + 4 - sqrt(4)`.

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13 can be made with `(4! / sqrt(4)) + (4 / 4)`, and 12 ((44 + 4) / 4) can be made with `4 x (4 - (4 / 4))`

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This is the last one: 4!-4^(4-4)

Isn’t that equal to 23?

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A correct one would be `4*4+4+4`.

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For some reason I didn’t write the pages in their natural order. There are 25 pages, two of them with the result 23. I can’t tell why, but I do remember that I was unhappy with 23. I suppose I may have ended up with two unsatisfying 23s. Which 23 to prefer is then not my decision.