INORDER = pa pb pc pd;
OUTORDER = pe pf pg ph pi pj pk pl pm pn;
pe = [45] + !no0;
pf = [46] + !no0;
pg = [47] + !no0;
ph = [48] + !no0;
pi = [49] + !np0;
pj = [50] + !np0;
pk = [51] + !np0;
pl = [52] + !np0;
pm = !nn0 + pa;
pn = !nn0 + !pa;
nn0 = pd*[53];
no0 = !pc*!pd;
np0 = !pd*!no0;
[45] = pa + pb;
[46] = !pa + pb;
[47] = pa + !pb;
[48] = !pa + !pb;
[49] = pa + pb;
[50] = !pa + pb;
[51] = pa + !pb;
[52] = !pa + !pb;
[53] = !pc*!pb;