which code is giving you always the same key? it seems not probable to me. In case post your code , your data and your output.

Here mines: 

#cat gen1.txt
@gi
AGAT
+
AAAA    1:1.txt

@gi
CATT
+
AAAAA    3:1.txt
#cat gen2.txt
@gi
AGAT
+
AAAA    1:2.txt

@gi
TACA
+
AAAA    2:2.txt

perl  -lane "BEGIN{$/=''}map{$h{$_}{s}.=' '.$F[4];$h{$_}{c}+=$1 if $F[
+4]=~/(\d+):/}join qq(\n),@F[0..3];
             END{print map{qq($_ $h{$_}{c} $h{$_}{s}\n\n)} keys %h}"  
+  gen1.txt gen2.txt


@gi
AGAT
+
AAAA 2  1:1.txt 1:2.txt

@gi
CATT
+
AAAAA 3  3:1.txt

@gi
TACA
+
AAAA 2  2:2.txt

[download]

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re^5: preserving hash value outside the loop -- silly oneliner by Discipulus
in thread preserving hash value outside the loop by Anonymous Monk

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