T1:=REF(C=O;T2:=REF(C=O,1) AND C>=O;T3:=REF(C=O,2) AND REF(C>=O,1) AND C>=O;T4:=REF(C=O,3) AND REF(C>=O,2) AND REF(C>=O,1) AND C>=O;T5:=REF(C=O,4) AND REF(C>=O,3) AND REF(C>=O,2) AND REF(C>=O,1) AND C>=O;T6:=REF(C=O,5) AND REF(C>=O,4) AND REF(C>=O,3) AND REF(C>=O,2) AND REF(C>=O,1) AND C>=O;T7:=REF(C=O,6) AND REF(C>=O,5) AND REF(C>=O,4) AND REF(C>=O,3) AND REF(C>=O,2) AND REF(C>=O,1) AND C>=O;T8:=REF(C=O,7) AND REF(C>=O,6) AND REF(C>=O,5) AND REF(C>=O,4) AND REF(C>=O,3) A