use strict;
use warnings;
# From http://prometheus.frii.com/%7Egnat/yapc/2000-stages/slide31.htm
+l
# Fixed a typo in the regex (Nathan forgot to escape the forwardslash.
+)

while (<DATA>) {
  chomp;
  my $celsius = my $fahrenheit = $_;
  #was $fahrenheit =~ s|(\d+)C|($1*9/5)+32 . "F"|ge;
  $fahrenheit =~ s|(\d+\.\d+)C|($1*9/5)+32 . "F"|ge;
  print "$celsius is $fahrenheit\n";
}
#Outputs: 
#12C is 12C
#16.5C is 61.7F
#-40C is -40C

__DATA__
12C
16.5C
-40C

[download]
UPDATE: Fixed regex to find decimals, after JDPorter pointed out the problem below. (And before Tanktalus beat me to it ;) )

In reply to Celsius to Fahrenheit using s/// by tphyahoo

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