my @e =
   grep !$_,
      map $_ % 2,
         @c;

##</code><code>##

my @e =
   map $_ % 2 ? () : 0,
      @c;

##</code><code>##

my @e;
for my $c ( @c ) {
   my $d = $c % 2;
   push @e, $d if !$d;
}

##</code><code>##

my @e;
for my $c ( @c ) {
   push @e, 0 if !( $c % 2 );
}

##</code><code>##

my @e = ( 0 ) x grep !( $_ % 2 ), @c;

##</code><code>##

my @e; push @e, 0 for 1 .. grep !( $_ % 2 ), @c;