search( key, t )
	typekey key;
	btree t;

	{	int i;
	while (t != NULL)	{
		for (i=0; i<t->d && key>t->k[i]; i++);
		if (key == t->k[i])
			{ found( t, i );	return; }
		t = t->p[i];
		}
	notfound( key );
	};