I think you need to get acquainted with "use strict". It might lead you to prefer using fewer variables overall, which would be a good thing. As for the logic in the OP, I'm puzzled. You say the ordering of input lines could be arbitrary, yet you have conditions based on the input line number. Apart from that, the "unless" block at the end is doing something that has no effect on the output: you change the value of $v2 and then don't use the modified value at all.

Here's a variant similar to the first reply, but with less typing: 

use strict;
my @outputs;

while (<DATA>) {
    my @fields = split;
    push @fields, '' if ( @fields == 3 );
    for my $i ( 0..$#fields ) {
        $outputs[$i] .= $fields[$i] . '|';
    }
}
chop @outputs;   # remove final '|';
print "$_\n" for ( @outputs );

__DATA__
ID1 > 66
ID2 between 6 10
ID3 < 7

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In reply to Re: Building up a string from a text file by graff
in thread Building up a string from a text file by joec_

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