I am attempting to use regex on a text file that will match two numbers that represent temperature in Celsius. I attempted to put the numbers in two separate capture groups and then put them inside a formula to convert to Fahrenheit. I would then set two variables equal to two separate formulas with each using one of the capture groups. The point of this is to take a line like this:

KSMO 181551Z 00000KT 10SM CLR 14/08 A3009 RMK AO2 SLP189 T01440083

and take the "14/08" to convert it to Fahrenheit and substitute it back into the line. When I run my code I receive these errors:

Odd number of elements in anonymous hash at lab2-2.pl line 11.

Use of uninitialized value $1 in anonymous hash ({}) at lab2-2.pl line 11.

Odd number of elements in anonymous hash at lab2-2.pl line 12.

Use of uninitialized value $2 in anonymous hash ({}) at lab2-2.pl line 12.

readline() on closed filehandle IN at lab2-2.pl line 13.

I am wondering what I am missing. Is it an issue with my regex or somewhere else? Any help would be appreciated.

#usr/bin/perl

use strict;
use warnings;

open IN,'<',"part2.txt";
open OUT,'>',"airport_fahrenheit.txt";

my $x;
my $fahrenheit1 = (9 *{$1}/5) + 32;
my $fahrenheit2 = (9 *{$2}/5) + 32;
foreach $x (<IN>){
  ( $x =~ s/(\d\d)\/(\d\d)/$fahrenheit1\/$fahrenheit2/g );
  print OUT "$x";
}
close IN;
close OUT;

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In reply to substitution with regex by drose2211

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