there is nothing printing into the txt file.
is there anything obviously wrong ?
I know the pattern matching code is right.

#!/usr/local/bin/perl 

while( my $file = <graph_set_*.out> ) {
    next unless $file =~ m[graph_set_[123]?[0-9].out];
    open IN, '<', $file 
        or warn "Couldn't open file $file because $!";
  
local $/ = undef;       # undef record seperator
my $string = <IN>;         # read whole file into string    
close IN;
}

my @gset_match = ($string =~ /([A-Z]\s\d+,\s\d+\(\s*\d+\))/g);

open (TEXT, ">graph_set.txt") or die "Can't create graph_set.txt: $!\n
+";
foreach $_(@gset_match) { print TEXT "$_\n"; }
close TEXT;
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