Algo(T,L)
	ct=null st=null
	cx=null sx=null
	cp=null sp=null
	cld=null sld=null
	cl=null

	next=null
	last=null
	ret=null
	while(ct!=null || st!=null) then
		if(ct!=null) then
			cp=ct->k%2
			sp=push(cp,sp)
			st=push(ct,st)
			next=ct->dx
		else
			ct=top(st)
			if(ct->sx!=null && ct->sx!=last) then
				cld=ret
				if(cp=0)then
					cx=NEW-NODE(ct->k)
					sx=push(cx,sx)
					sld=push(cld,sld)
					cl=cx
				else
					cl=cld
				next=ct->sx
			else
				cp=top(sp)
				if(ct->sx!=null) then
					cl=ret
					if(cp=0) then
						cld=top(sld)
						cx->next=cld

				else
					cld=ret
					cl=null
					if(cp=0) then
						cx=NEW-NODE(ct->k)
						cld=top(sld)
						cx->next=cld

				ret=cl
				next=null
				pop(di tutto)
		last=ct
		ct=next