Re: [Haskell-cafe] Re: New slogan for haskell.org

apfelmus wrote:

Henning Thielemann wrote:

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apfelmus wrote:

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Back then, I was given the task to calculate some sequence of numbers which I did in one page of C code. So far so good, but when I asked the task assigner about his solution, he responded: "Ah, this problem, that's 1 line in Haskell. Well, 2 lines if the terminal is too small."

Ah, a Haskell code contribution to the Encyclopedia of Integer Sequences?

The task was just for fun, but it's sequence A050000.

import Data.Set xs = let f x m = x: let y = x `div` 2 in f (if member y m then 3*x else y) (insert x m) in f 1 (singleton 0)

As said, it's two lines if the terminal is too small :)

I can't see how it could be one page of C unless the page is 10 lines long ;-) The following code is the direct translation of your Haskell code (except that it prints the result instead of building a list). a+, ld. #include #include void f(int x, intset s) { printf("%d, ", x); f (intset_elem(s, x/2) ? 3*x : x/2, intset_put(s, x)); } int main(void) { f (1, intset_put(intset_new(), 0)); }