Roger, I'd definitely love to see your code in the mathschallenge forum(yes, I have solved it myself). I'm interested in seeing how you keep and update the (hash?) table efficiently.
2006/9/4, Roger Hui <[EMAIL PROTECTED]>:
Sorry, typo: f^:(i&<:)^:a: i The constructs f^:proposition^:_ f^:proposition^:a: are tacit versions of "do while" and can be useful. ----- Original Message ----- From: Roger Hui <[EMAIL PROTECTED]> Date: Sunday, September 3, 2006 5:00 pm Subject: Re: [Jprogramming] Mathschallenge Problem 14 > My solution is 16 lines and takes 23 seconds on a > 2.2 GHz Athlon. > > a. Use for_i. i.n instead of while. > > b. Use a [EMAIL PROTECTED] verb instead of control structures > to implement the logic > if odd do 1+3*n > if even do n%2 > > c. Use f^:^:(i&<:)^:a: i to get the entire sequence > on its way from i to j where j is less than i and > already in the table; update the table using the > entire sequence. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
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