Re^2: Sorting unique values in file using perl

[PerlSavvy]

my $file1="file1.txt";
open FILE1, "<$file1" or die $!;

my $file2="min_viols_endpointSorted.csv";
open FILE2, ">$file2" or die $!;


while(<FILE1>){ 
my $path = $_; 
$path =~ /([^\s]+)/; 
$path = $1; #Extracting path 
chop($path); 
my $slack = $_; 

$slack =~ /[^\f+][\s+][\f+][\s+][\f+][\s+]([\f+]+)[\s](VIOLATED)/; 
$slack = $1; 
print "$slack\n"; 
chop($slack); 
print FILE2 "$path $slack\n"; 
}

After this I plan to read the csv into a hash and compare the values of hash keys. If one hash value for a duplicate key is less than previous value than put it in a output file. And output should be unique, as I have shown in my question. Please help on this.

[jwkrahn]

$path =~ /([^\s]+)/; 
$path = $1; #Extracting path 

...

$slack =~ /[^\f+][\s+][\f+][\s+][\f+][\s+]([\f+]+)[\s](VIOLATED)/; 
$slack = $1;

You shouldn't use the results of a regular expression unless you verify that the pattern matched or you may get erroneous results.    Also /([^\s]+)/ is usually written as /(\S+)/ and /[^\f+][\s+][\f+][\s+][\f+][\s+]([\f+]+)[\s](VIOLATED)/ matches a single character that is not a FORM FEED or '+' character, followed by a whitespace or '+' character, followed by a FORM FEED or '+' character, etc., but there are no FORM FEED characters in the string.





chop($path); 

...

chop($slack);

chop removes the last character of the string, no matter what it is.    So what is the purpose of removing the last character from $path or $slack?