Some code to get you started. 

use strict;
use warnings;

my $eq = '2+3x+7x(x+27)-6';
my @mult=(1);
my @pow=(0);
my @c;
# die "Not supported.\n" if /[^-+0-9x]/;
die "Not supported: '$1' \n" if $eq =~ /([^-+0-9x()]+)/; # as per Anom
+alousMonk's suggestion
print "Equation: $eq\n";
while($eq=~/([-+]?)(\d*)(x?)([)(]?)/g){
  next unless "$1$2$3$4";
  my $d = $2 || 1;
  $d *= -1 if $1 eq '-';
  if( $4 eq '(' ) {
    push @mult, $mult[-1]*$d;
    push @pow, $pow[-1]+1;
  } else {
    if( $3 ) {
      $c[1+$pow[-1]] += $mult[-1]*$d;
    } else {
      $c[$pow[-1]] += $mult[-1]*$d;
    }
  }
  if( $4 eq ')' ) {
    pop @mult;
    pop @pow;
  }
}
print "Summary: @c\n";

[download]

In reply to Re: How would you solve a user-inputted simple one-variable Linear Equation by hdb
in thread How would you solve a user-inputted simple one-variable Linear Equation by nat47

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.