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Rust

I enjoyed the bit at the end where the writer managed to use the wrong (IMO) formula to arrive at the correct answer.

Using BEDMAS as I was taught, so many moons ago:

6 ÷ 2 ( 1 + 2 )

6 ÷ 2 ( 3 )

6 ÷ 2 * 3 // because 2(3) is not an exponent or algebraic construct, it's straight multiplication

3 * 3 // division and multiplication are in left-to-right order, no precedence

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Update: after reading the article at http://www.matthewcompher.com/posts/trouble-with-semantics-t... , the writer used the ÷ as a line operator, not a natural division operation.

I would maintain that since this is not taught in any school I've ever attended, it is at least questionable. I've never seen a math textbook use the / symbol for natural division either.

I never knew about the distinction either. But if interpreted that way

    6 ÷ 2 (1 + 2)

should then translate to

    6 / (2 * (1 + 2)) = 1

I guess this only reaffirms the fact that the expression is ambiguous.

that seems wrong to me too, either I lost my math or I don’t see how he went from

   6 ÷ 2 (1 + 2)

   (6 * (1 + 2)) / 2

You may reorder factors arbitrarily

  *a /b *c = *a *b /c = /c *b *a  etc.

  so 6 /2 *(...) = 6 *(...) /2.

Right. Silly me. What a weird way of doing it though.

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