You don't show us the code with the counter, so it's hard to say where you went wrong. Here's a loop that starts with opening graph_set_1.out, and continues to increase the number until there's no matching file. 
for (my $c = 1;; $c ++) {
    my $file = "graph_set_$c.out";
    last unless -f $file;
    open my $fh => "<", $file or die "Failed to open $file: $!";
    ...  # Do something with $fh.
}

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Abigail

In reply to Re: opening consecutive files by Abigail-II
in thread opening consecutive files by harry34

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