my $i=0;
while ($i<$#group) {
    $hash{$group[$i]}=$group[$i+1];
    $i+=2;
    }

##</code><code>##

@destination = map {$_++} @source

##</code><code>##

.... = map { ("key$_" , "value$_") } .....

##</code><code>##

.... = map { ("key$_" => "value$_") } .....