my $elem = 1;
my $k = 3;
my %out;

while ( <DATA> ) {
   next unless /\b$elem\b/;
   $out{$_}++ for split;
}

delete $out{$elem};
print "$_ ($out{$_} times)\n" for 
   (sort { $out{$b} <=> $out{$a} } keys %out)[ 0 .. ( $k - 1 ) ];