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prefix notation question

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From	Chad <cdalten@gmail.com>
Newsgroups	comp.lang.java.programmer
Subject	prefix notation question
Date	Sun, 16 Oct 2011 20:15:19 -0700 (PDT)
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I'm supposed to write a program that calculates arithmetic expressions
using prefix notation. The one example our professor gave us is

(+ (- 6) (* 2 3 4) (/ (+ 3) (* 1) (- 2 3 1)))

Which evaluated sucessively becomes..

(+ (- 6) (* 2 3 4) (/ 3 1 -2)) //<----I don't see how he arrives at
this expression
(+ -6 24 -1.5)
16.5

I don't see how he gets (+ (- 6) (* 2 3 4) (/ 3 1 -2)) from (+ (- 6)
(* 2 3 4) (/ (+ 3) (* 1) (- 2 3 1)))

Chad

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prefix notation question Chad <cdalten@gmail.com> - 2011-10-16 20:15 -0700
  Re: prefix notation question Peter Duniho <NpOeStPeAdM@NnOwSlPiAnMk.com> - 2011-10-16 20:46 -0700
    Re: prefix notation question Chad <cdalten@gmail.com> - 2011-10-16 20:58 -0700
      Re: prefix notation question Peter Duniho <NpOeStPeAdM@NnOwSlPiAnMk.com> - 2011-10-16 23:38 -0700
      Re: prefix notation question Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2011-10-17 10:06 +0300
        Re: prefix notation question Chad <cdalten@gmail.com> - 2011-10-17 07:39 -0700
          Re: prefix notation question Chad <cdalten@gmail.com> - 2011-10-17 07:45 -0700
            Re: prefix notation question Chad <cdalten@gmail.com> - 2011-10-17 07:50 -0700
              Re: prefix notation question Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2011-10-17 18:10 +0300
                Re: prefix notation question Chad <cdalten@gmail.com> - 2011-10-18 15:30 -0700
                Re: prefix notation question Roedy Green <see_website@mindprod.com.invalid> - 2011-10-18 19:40 -0700
  Re: prefix notation question Roedy Green <see_website@mindprod.com.invalid> - 2011-10-18 19:36 -0700

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