原式=(2-1)+(3-2)+…+(9-8)
=2-1+3-2+…+9-8
=9-1
=3-1
=2.
故答案为:2.
Distinguished guests and friends, welcome to our school, _____ the ceremony of the 50th Anniversary this
morning are our alumni (校友) from home and abroad. [ ]
A. Attend
B. To attend
C. Attending
D. Having attended
在长度为n的顺序表的第i(1≤i≤n+1)个位置上插入一个元素,元素的移动次数为______。
A.n-i+1
B.n-i
C.i
D.i-1