#!/usr/bin/perl
use strict; use warnings;
use Sexpr;
use SexprNode;


my $sexprt = Sexpr->new;
$sexprt->read_wsjsynt(\*STDIN);

my @sexprn = $sexprt->dfs;
foreach my $n (@sexprn){
	print $n->{_label}, "\n";
}
print $sexprt->prettystring, "\n";