sub bubble {
   my $arrRef=shift;

   foreach my $i(1..@$arrRef-1) {
      @$arrRef[$i,$i-1]=@$arrRef[$i-1,$i] 
            unless $arrRef->[$i-1]<=$arrRef->[$i];
   }
}

sub isSorted {
   my $arrRef=shift;
   my $isSorted=0;

   foreach my $i(1..@$arrRef-1) {
      return 0 unless $arrRef->[$i-1]<=$arrRef->[$i];
   }

   return 1;
}

open(IN,"<raw_data") or die "Can't open raw_data, error $!";
my @raw_data=map {chomp;$_} <IN>;

print "Before sort: ",(join ",",@raw_data), "\n";
bubble(\@raw_data) while !isSorted(\@raw_data);
print "After sort: ",(join ",",@raw_data), "\n";