Here is my solution. It is no where as elegant and short as the previous ones. Comments on where I can improve this code and what practices I should stay away from are appreciated.
use strict; #OPEN FILE A.txt for READING (CHECK FOR FAILURES) open (INFILE, "<","A.txt" ) or die "Could not open file A.txt: $!"; #OPEN FILE B.txt for WRITING (CHECK FOR FAILURES) open (OUTFILE, ">","B.txt" ) or die "Could not open file B.txt: $!"; my $prev_country = ""; my $line; my @myarray; my $country; my $company; while ($line = <INFILE>) { # SPLIT THE FILE BETWEEN COUNTRY AND COMPANY @myarray = split /></,$line; $country = $myarray[0]; # CHECK TO SEE IF THE CURRENT COUNTRY MATCHS THE PREVIOUS COUNTRY if ($prev_country ne $country) { #IF NEW COUNTRY PRINT WHOLE LINE print OUTFILE "$line"; $prev_country = ($country); next; } # IF SAME COUNTRY PRINT ONLY COMPANY $company = $myarray[1]; print OUTFILE "\t<$company"; } close OUTFILE; close INFILE;

In reply to Re: replace all but first by terra incognita
in thread replace all but first by texuser74

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