use strict;

undef $/;
my $infile = (<>);

my @fields = $infile =~ /(".*?"|\n)/gms;

my $place = "\n";
foreach (@fields) {
  if ($place ne "\n" && $_ ne "\n") {print ",";};
  unless ($_ eq "\n") {s/\n//g;};
  print "$_";
  $place = $_;
}