ISBN 978-7-107-17648-7 is the book number of Compulsory Chemistry 2, a standard experimental textbook for senior high schools.

Please refer to the attachment for the information contest (the document cannot be inserted, please refer to the following).

Title: 1 information contest and introduction of some terms; Lesson preparation: Gai Jianhua comments:

Objective (1) To understand the background knowledge of the information contest and master the knowledge structure of the contest.

(2) will initially use the idea of information science to consider the problem.

Summary points: concepts such as knowledge structure, data structure and algorithm that need to be mastered in the competition.

Difficulties: Some terms and their connotations require a deep understanding of the concepts of data structures and algorithms.

Background knowledge 1 Informatics Olympic Competition, the full name of which is Youth Informatics (Computer) Olympic Competition (known as Youth Computer Programming Competition in the early days), is a subject competition activity aimed at popularizing computer education and computer application among young people. The National Informatics Olympic Competition is divided into three levels: First, the National Informatics (Computer) Olympic Division League (NOIP) is held, which is divided into high school group and junior high school group, with the main purpose of popularization. On the basis of regional leagues, provinces and cities form teams (usually 3 people) to participate in the second-level competition, that is, the National Youth Informatics Olympic Competition (NOI). At the third level, excellent players (usually 15) are selected from NOI, and after training and examination, the national team (usually 4-5 people) is formed. Participate in the International Informatics Olympic Competition, which is divided into two rounds: the initial test and the second test. The initial test is a written test, which focuses on students' basic computer knowledge and basic programming ability, and tests the breadth of knowledge. The preliminary examination is a qualification examination, and 0/5% of the students in the provinces/kloc-before the competition enter the semi-finals. The second interview takes the form of computer, focusing on students' ability to analyze and understand problems, mathematical abstraction, programming language ability and programming skills, imagination and creativity. The first prize of the provincial league is produced among the winners of the second interview.

2 Preliminary contents and requirements

▲ Basic knowledge of computer

1. Computer and information society (main features of information society, main features of computers, main features of digital communication networks, digitalization)

2. Basic principles of information input and output (information exchange environment, input and output methods of text and graphic multimedia information)

3. Information representation and processing (information coding, MPU, memory structure, instruction, program, principle of stored program and three basic control structures of program).

4. Information storage, organization and management (storage medium, storage structure, file management, database management)

5. Information system composition and basic knowledge of Internet (computer composition principle, extensible interconnection mode between slots and ports, hierarchical interconnection structure, Internet, TCP/IP protocol, HTTP protocol, main modes and characteristics of WEB application).

6. Basic concepts of human-computer interaction interface (window system, ways of exchanging information between people and computers (text and interactive operation))

7. New development, new features and new applications of information technology.

▲ Basic computer operation

Basic operating knowledge of Windows and LINUX.

2. Basic knowledge of Internet use (online browsing, search and query, etc. )

3. Use common tools and software (text editing, e-mail sending and receiving, etc.). )

▲ data structure

Basic data types in 1. programming language (character, integer, long integer, floating point)

2. Comparison of precision and numerical value in floating-point operation

3. One-dimensional array (string) and linear table

4. Record Type (Pascal)/Structure Type (C)

▲ programming

1. Basic concepts of structured programming

2. Basic ability to read and understand programs

3. Have the basic ability to abstract simple problems into models suitable for computer solution.

4. Have the basic ability to design simple algorithms for models.

5. Program flow description (natural language/pseudocode /NS diagram/others)

6. Programming language (PASCAL/C/C++, and BASIC was allowed in 2003)

▲ Basic algorithm processing

1. Elementary algorithm (counting, statistics, mathematical operation, etc. )

2. Sorting algorithm (bubble method, insert sorting, combined sorting and quick sorting)

3. Search (sequential search, dichotomy)

4. Backtracking algorithm

Preview before class and talk about your understanding of the following concepts.

(1)TCP/IP protocol (2) data structure

(3)PASCAL language (4) algorithm

think

Explore 1, think and answer the following situational questions:

TCP/IP is a communication protocol for computers connected to the Internet. TCP/IP defines how electronic devices (such as computers) are connected to the Internet and how data is transmitted between them. When data is transmitted through TCP/IP protocol, we can take the processing of letters as an analogy. Data like _ _ _ _ _. An IP address is like _ _ _ _ _ _ _. TCP ports are like _ _ _ _ _ _ _. If someone does not abide by the agreement, or sends a lot of information to all groups, or sends a lot of information to someone, which eventually leads to network congestion or paralysis, this is called _ _ _ _ _ _ _ _.

In programming, arrays can be analogized by mathematical series. Let the general formula of the sequence {an} be an = 4n+1(n >; = 1), then a=8, then the general formula a[m, n](m, n takes 1...4) is _ _ _ _ _ _ _ _ _ _ _ _ (expressed by m, n).

1 4 9 16

1 2 3 4

25 36 49 64

5 6 7 8

Recursive algorithm is a method to describe complex problems with simple operations (rules), which can be repeated in several steps. For example, the cube of any natural number should be written as the sum of a series of consecutive odd numbers. Recursion can be performed as follows:

13= 1

23=3+5=8

33=7+9+ 1 1=27

43= 13+ 15+ 17+ 19=64

……………………….

Let n be an arbitrary natural number, its cube is the sum of m odd numbers, and the first odd number is p, then n3 = p+_ _ _ _+...+_ _ _ _. n+1cube consists of the sum of _ _ _ _ _, where the first odd number is _ _ _ _ _. In addition, when n= 1, m = _ _ _ _, p = _ _ _.

(1) How to square the elements in array a[n] to represent a new array?

(2) In descending order {1, 5, 9, 1 1, 8}.

(3) Analogous letters, what address information should the data contain after being assembled according to TCP/IP protocol?

(4) If someone doesn't realize his own network communication according to the customized protocol, what protocol does he use?

(5) If recursive algorithm is not used, can the expression of n3 be obtained by mathematical induction? Can you feel some differences between computer processing method and mathematical thinking method?

Explore new knowledge and think about the following questions:

1 Suppose there is an array with eight elements {1, 5,10,20,15,8,6,90}.

Observing its characteristics, it is found that all the elements in it are _ _ _ _ _ _, and they are organized in the form of _ _ _ _. We call these ordered sets of similar data elements arrays.

On the basis of integer array, we can define some standard operations, such as finding the maximum and minimum number, sorting and so on. Let's have a look. What other operations can be defined on the array?

Therefore, in computer science, data structure is a subject that studies the operating objects (data elements) of computers and their relations and operations in non-numerical computing programming problems, and ensures that the new structure obtained after these operations is still the original structure type.

In addition, we can also examine the data structure from the perspective of sets and functions. For example, the elements of the above array can form a set, and the relationship between them in order, size and sorting can be understood as _ _ _ _ _ _ _ _.

A data structure can be formally defined as (k, r) (or (d, s)), where k is a finite set of data elements and r is a finite set of relationships on k.

2 Through the example of recursive algorithm above, we summarized the characteristics of the algorithm:

Algorithm is a series of clear instructions to solve the problem, that is, it can get a standard _ _ _ _ _ in a limited time. The algorithm can be understood as a complete problem-solving step, which consists of basic operation and specified operation sequence. Or a finite and accurate calculation sequence designed according to the requirements. Such steps and sequences can solve a class of problems.

An algorithm should have the following five important characteristics:

1, finiteness: an algorithm must be guaranteed to end after a finite number of steps;

2. Accuracy: Every step of the algorithm must have an accurate definition;

3. Input: An algorithm has zero or more inputs to describe the initial situation of the operation object. The so-called zero input means that the algorithm itself excludes the initial conditions;

4. Output: An algorithm has one or more outputs to reflect the results of processing input data. An algorithm without output is meaningless;

5. Feasibility: In principle, the calculation method can run accurately, and it can be completed after a limited number of calculations with paper and pencil.

Illustration [example 1] On Arbor Day, five people participated in tree planting activities, and the number of trees they planted was different. Asked how many trees the first classmate planted, he pointed to the second classmate next to him and said that he planted two more trees. Questioning the second classmate, he said that he planted two more trees than the third classmate; ... so, it is said that two more trees were planted than another classmate. Finally, I asked the fifth classmate, and he said that he planted 10 trees. How many trees did the first classmate plant?

[Example 2] Faibonacci) 0 series (0, 1, 1, 2, 3, 5, 8, 13, 2 1, 34 ... Find the nth item in this series.

[Example 3] Find all prime numbers within 25 by screening method.

[Example 4] Enter the test scores of four students in five courses: Mathematics, Physics, English, Chemistry and Pascal, find out the average score of each student, and print out the form.

In-class feedback exercise 1, calculator, controller and memory of microcomputer are collectively called _ _ _ _.

A) central processing unit b) arithmetic logic unit

C) microprocessor d) host

2, reflect the basic unit of computer storage capacity is _ _ _ _.

A) binary bits b) bytes

C) words d) double words

3, decimal number 123 into equivalent binary number is _ _ _ _.

a) 1 10 10 1 B) 1 10 1 10

c) 1 1 10 1 1D) 1 100 1 1

4. Delete an element in the array, and all the elements on the right move one space to the left.

Summary 1. To learn information science well, on the one hand, we should have a general knowledge of computer composition, network and operating system, on the other hand, we should learn to program to make computers listen to your instructions. In addition, data structures and algorithms are the soul of information competition.

2. You can deeply understand the thinking characteristics of information science from recursive algorithm.

Students' reflection

Homework after class 1, monkeys eat dates: the monkey picked a bunch of dates, ate half of them on the first day, but it was not enough, and ate another one; The next day, I ate the remaining half and one; Every day from now on. On the tenth day, the monkey saw that only one was left. How many dates did you have at first?

2. The stairs have n steps. You can go upstairs one step at a time or two steps at a time. How many different ways are there to calculate * * *?

3. Rabbits can reproduce two months after birth. Suppose a pair of rabbits can give birth to a pair of rabbits every month, and each pair of rabbits will give birth to a pair of rabbits every month two months after birth. So, how many pairs of rabbits are there in a given month, starting with a pair of newborn rabbits and continuing to breed?

4. Enter m integers into a one-dimensional array, assuming that M=6, and the array elements are 7489 1.5 respectively.

The following arrays (matrices) need to be created:

7 4 8 9 1 5

4 8 9 1 5 7

8 9 1 5 7 4

9 1 5 7 4 8

1 5 7 4 8 9

5 7 4 8 9 1