thuc ra bai nay suy luan la khong kho.kho nhat la tu duy cua nguoi ra de.dap an chi xuat hien khi dien day du thong tin cua tat ca moi nguoi.dung la anhxtanh qua gioi.hon nua giai dc bai toan nay cung khong phai la 2% gi do.ma anhxtanh chi muon chung ta dam me cai gi do 1 cach thuc su.hay cuon minh vao cong viec bang toan bo cai dau.
