【单选题】The reason _____ the president of Czech is widely discussed recently is _______ he was seen “to steal” a pen at a press conference in Chile.
【单选题】Although he is considered a great writer, _____.
A.
however his works are not widely read
B.
but his works are not widely read
C.
his works are not widely read
D.
still his works are not widely read
【简答题】假设一棵含有13个结点的完全二叉树中,按层次从上到下、每层结点从左到右的顺序,从0开始编号,则编号为4的结点的右孩子编号为_______(如果孩子不存在,则填写NULL)。
【简答题】曲线y=xe -x 的拐点是______.