oh yes the reverse if for sure the best trick, but you can eliminate entirely the while loop using map instead.

#! perl
use strict;
use warnings;
use Data::Dump;


my @A = qw ( H1 H2 H3 H4);
my @B = qw (1 2 3 4 5 6 7 8 9 10);

my %h;

map {push @{$h{ $_ }},grep {defined} shift @B} (@A, reverse @A) x int 
+($#B / $#A) ;

dd %h;

[download]


L*
UPDATE: with help of choroba i realized i had no need of int nor of so much repetitons: 

   map {push @{$h{ $_ }}, shift @B} (@A, reverse @A) x ($#B / $#A /2) 
+;  ##No it is still not good..

[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^3: How to get this not the usual round robin looping bustrophedon semplified by Discipulus
in thread How to get this not the usual round robin looping by fidda

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