Once there was a huge apple tree. A litt

题型:阅读理解

问题:

Once there was a huge apple tree. A little boy loved to come and play around it every day. He loved the tree and the tree loved to play with him.

Time went by — the little boy had grown up and he no longer played around the tree every day. One day, the boy came back to the tree and he looked sad. “Come and play with me,” the tree asked the boy. “I’m no longer a kid. I wouldn’t play around the tree any more.” the boy replied. “I want toys. I need money to buy them.” “Sorry, I don’t have money. But you can pick all my apples and sell them. So, you will have money.” The boy picked all the apples on the tree and left happily. The boy never came back after he picked the apples.

One day, the boy returned and the tree was so excited, “Come and play with me,” the tree said. “I don’t have time to play. I have to work for my family. We need a house for shelter. Can you help?” “Sorry, I don’t have a house. But you can cut off my branches to build your house.” So the boy cut all the branches off the tree and left happily. The tree was glad to see him happy but the boy never came back since then. The tree was again lonely and sad.

One hot summer day, the boy returned and the tree was pleased. “Come and play with me!” the tree said. “I am sad and getting old. I want to go sailing to relax myself. Can you give me a boat?” “Use my trunk to build your boat. You can sail far away and be happy.” So the boy cut the tree trunk to make a boat. He went sailing and never showed up for a long time.

Finally, the boy returned after he left for so many years. “Sorry, my boy. But I don’t have anything for you any more. The only thing left is my dying root,” the tree said with tears ①

“Good! Old tree root is the best place to lean on and rest. Come and sit down with me and rest.” The boy sat down and the tree was glad and smiled with tears ② ……

小题1:Why did the boy pick all the apples on the tree? Because __________.

A.he wanted to eat them

B.he needed money to buy toys

C.he liked the tree without apples

D.he wanted to share them with friends.小题2:When did the boy come back to the apple tree? He came back _________.

A.whenever he was happy

B.if he missed the apple tree

C.when he was in times of difficulty

D.as soon as he was free小题3:What did the boy want at last? He wanted ___________.

A.to have a house to live in

B.nothing except a place to rest

C.the root of the apple tree

D.anything that the apple tree had小题4:What can we learn from the story? We should _________.

A.plant more apple trees

B.learn from the boy

C.always stay at home

D.be thankful to our parents小题5:According to the passage, which of the following is NOT true?

A.The phrase “with tears ①” means that the apple tree was sad because the boy asked for too much.

B.The phrase “with tears ②” means that the apple tree was still happy because she could help the boy for the last time.

C.Each time the boy asked the apple tree for help, the tree tried her best to satisfy him.

D.After reading the passage, we can easily think of the old Chinese saying “Parents’ love is universal!”

考点:人生感悟类阅读
题型:阅读理解

阅读下列说明,回答问题1至问题3,将解答填入对应栏内。

[说明]

快速排序是一种典型的分治算法。采用快速排序对数组A[p..r]排序的3个步骤如下:

(1)分解:选择一个枢轴(pivot)元素划分数组。将数组A[p..r]划分为两个子数组(可能为空)A[p..q-1]和A[q+1..r],使得A[q]大于等于A[p..q-1]中的每个元素,小于A[q+1..r]中的每个元素。q的值在划分过程中计算。

(2)递归求解:通过递归的调用快速排序,对子数组A[p..q-1]和A[q+1..r]分别排序。

(3)合并:快速排序在原地排序,故不需要合并操作。

[问题1]

下面是快速排序的伪代码,请填补其中的空缺。

伪代码中的主要变量说明如下:

A:待排序数组;

p,r:数组元素下标,从p到r;

q:划分的位置;

x:枢轴元素;

i:整型变量,用于描述数组下标。下标小于或等于i的元素的值小于或等于枢轴元素的值:

j:循环控制变量,表示数组元素下标。

QUICKSORT(A,P,r)

if(p<r)

q=PARTITION(A,p,r);

QUICKSORT(A,p,q-1);

QUICKSORT(A,q+1,r);

PARTITION(A,p,r)

X=A[r];i=p-1;

for(j=p;j≤r-1;j++)

if(A[j]≤x)

i=i+1;

交换A[j]和A[j]

交换 (1) (2) //注:空(1)和空(2)答案可以互换,但两个空全部答对方可得分

return (3)

[问题2]

(1)假设要排序包含n个元素的数组,请给出在各种不同的划分情况下,快速排序的时间复杂度,用O记号。最佳情况为 (4) ,平均情况为 (5) ,最坏情况为 (6)

(2)假设要排序的n个元素都具有相同值时,快速排序的运行时间复杂度属于哪种情况 (7) 。(最佳、平均、最坏)

[问题3]

(1)待排序数组是否能被较均匀地划分对快速排序的性能有重要影响,因此枢轴元素的选取非常重要。有人提出从待排序的数组元素中随机地取出一个元素作为枢轴元素,下面是随机化快速排序划分的伪代码——利用原有的快速排序的划分操作,请填充其中的空缺处。其中,RANDOM(i,j)表示随机取i到j之间的一个数,包括i和j。

RANDOMIZED-PARTITION(A,p,r)

i=RANDOM(p,r);

交换 (8) (9) ;//注:空(8)和空(9)答案可以互换,但两个空全部答对方可得分

return PARTITION(A,p,r);

(2)随机化快速排序是否能够消除最坏情况的发生 (10) 。(是或否)

(5)处填()。

题型:阅读理解

母乳喂养至少坚持到新生儿出生后()

A.2~3个月

B.3~4个月

C.4~6个月

D.6~8个月

E.12个月

题型:阅读理解

中华人民共和国的根本制度是( )。

A.民主集中制

B.劳动群众集体所有制

C.社会主义制度

D.人民代表大会制度

题型:阅读理解

非牛顿型流体大致可以分为几类?

题型:阅读理解

计算机网络是以能够相互共享资源的方式互联起来的 【4】 系统的集合。

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