#!/usr/bin/perl -s

use strict;
our ($i);
my $enpt =0;
my $pten =1;
if($i){ ($enpt,$pten)=(1,0) }
undef $/;
while(<>){
  if($pten){print pten($_)}
  if($enpt){print enpt($_)}
}

sub enpt{my $linha=shift;
  $linha =~ s!(#[MFCSBX]+)! $1 =~ y/MFCSB/MPFSI/r !ge;
  $linha
}

sub pten{my $linha=shift;
  $linha =~ s!(#[MPFSIX]+)! $1 =~ y/MPFSI/MFCSB/r !ge;
  $linha
}

__END__
#/
#=
#doc
#bio
#dono  owns
#mecenas_de mecenas_of
#morou   lived_in 
#ver-doc in-doc