ccccccccc

struct tstk {
	int inf;
	tstk *a;
}*a, *b;

tstk *AddStask(tstk  *sp, int inf) {
	tstk *spt = new tstk;
	spt->inf = inf;
	spt->a = sp;
	return spt;
}

tstk *ReadStackD(tstk *sp, int &inf) {
	if (sp == NULL) return NULL;
	tstk *spt = sp;
	inf = sp->inf;
	sp = sp->a;
	delete spt;
	return sp;
}

tstk *DelStackAll(tstk *sp) {
	tstk *spt; int inf;
	while (sp != NULL) {
		spt = sp;
		inf = sp->inf;
		sp = sp->a;
		delete spt;
	}
	return NULL;
}
void RevStackAfter(tstk *sp)
{
	tstk *spt = sp->a->a;
	sp->a->a = spt->a;
	spt->a = sp->a;
	sp->a = spt;
}