home biology tutor Exam variant in computer science with a solution. Proper preparation for the exam in computer science from scratch. What is the exam in computer science

Exam variant in computer science with a solution. Proper preparation for the exam in computer science from scratch. What is the exam in computer science

For effective training in computer science for each task, a brief theoretical material is given to complete the task. Matched over 10 training tasks with analysis and answers, developed on the basis of the demo version of previous years.

There are no changes in KIM USE 2020 in informatics and ICT.

The areas in which the knowledge test will be carried out:

Programming;
Algorithmization;
ICT tools;
Information activity;
Information processes.

Necessary actions when preparing:

Repetition of the theoretical course;
Solution tests in informatics online;
Knowledge of programming languages;
Pull up mathematics and mathematical logic;
Use a wider range of literature - school curriculum not enough to succeed in the exam.

Exam Structure

The duration of the exam is 3 hours 55 minutes (255 minutes), of which one and a half hours are recommended to be devoted to completing the tasks of the first part of the KIMs.

Tasks in tickets are divided into blocks:

Part 1- 23 tasks with a short answer.
Part 2- 4 tasks with a detailed answer.

Of the proposed 23 tasks of the first part examination work 12 refer to the basic level of knowledge testing, 10 - advanced complexity, 1 - high level of complexity. Three tasks of the second part high level complexity, one - increased.

When solving, it is obligatory to record a detailed answer (arbitrary form).
In some tasks, the text of the condition is submitted immediately in five programming languages - for the convenience of students.

Points for tasks in computer science

1 point - for 1-23 tasks
2 points - 25.
3 points - 24, 26.
4 points - 27.
Total: 35 points.

To enter a technical university of an intermediate level, you must score at least 62 points. To enter the metropolitan university, the number of points must correspond to 85-95.

To successfully write an examination paper, you need a clear command of theory and constant practice in solving tasks.

Your formula for success

Work + work on mistakes + carefully read the question from beginning to end to avoid mistakes = maximum score on the exam in computer science.

Which programming language to choose, what tasks to focus on and how to allocate time on the exam

Teaches computer science at Foxford.

Different universities require different entry exams in IT areas. Somewhere you need to take physics, somewhere - computer science. It is up to you to decide which exam to prepare for, but it should be borne in mind that the competition for specialties where physics must be taken is usually lower than in specialties where the Unified State Examination in computer science is required, i.e. the probability of entering "through physics" is greater.

Why then take the exam in computer science?

It is faster and easier to prepare for it than for physics.
You will be able to choose from more specialties.
It will be easier for you to study in the chosen specialty.

What you need to know about the exam in computer science

The exam in computer science consists of two parts. In the first part there are 23 problems with a short answer, in the second - 4 problems with a detailed answer. The first part of the exam has 12 basic level items, 10 advanced level items and 1 high level item. In the second part - 1 task of an increased level and 3 - high.

Solving problems from the first part allows you to score 23 primary points - one point for the completed task. Solving problems of the second part adds 12 primary points(3, 2, 3 and 4 points for each task, respectively). Thus, the maximum primary points that can be obtained for solving all tasks is 35.

Primary scores are converted into test scores, which are USE result. 35 primary points = 100 test points per exam. At the same time, more test points are awarded for solving problems from the second part of the exam than for answers to the problems of the first part. Each primary score obtained for the second part of the exam, will give you 3 or 4 test scores, for a total of about 40 final scores for the exam.

This means that at fulfillment of the exam in informatics should be given Special attention solving problems with a detailed answer: No. 24, 25, 26 and 27. Their successful execution will allow you to score more points. But the price of a mistake during their implementation is higher - the loss of each primary score is fraught with the fact that you will not pass the competition, because 3-4 final scores for the Unified State Examination with high competition in IT specialties can become decisive.

How to prepare for solving problems from the first part

Pay special attention to tasks No. 9, 10, 11, 12, 15, 18, 20, 23. It is these tasks, according to the analysis of the results of past years, that are especially difficult. Difficulties in solving these problems are experienced not only by those who have a low overall score for the Unified State Examination in computer science, but also by “good students” and “excellent students”.
Learn by heart the table of powers of the number 2.
Remember that Kbytes in tasks means kibibytes, not kilobytes. 1 kibibyte = 1024 bytes. This will help avoid calculation errors.
study carefully USE options previous years. The computer science exam is one of the most stable, which means that you can safely use the USE options for the last 3-4 years for preparation.
Get to know the different options for wording assignments. Remember that a slight change in the wording will always lead to worse exam results.
Read the problem statement carefully. Most of the errors in completing assignments are due to a misunderstanding of the condition.
Learn to independently check completed tasks and find errors in the answers.

What you need to know about problem solving with a detailed answer

24 task - to find the error

25 task requires a simple program

26 task - on game theory

27 task - it is necessary to program a complex program

Problem 27 is the main difficulty in the exam. It is only decided60-70% of USE writers in computer science. Its peculiarity lies in the fact that it is impossible to prepare for it in advance. Each year, a fundamentally new problem is presented for the exam. When solving problem No. 27, not a single semantic error should be made.

How to calculate exam time

Be guided by the data that are given in the specification of control measuring materials for conducting the exam in informatics. It indicates the approximate time allotted for completing the tasks of the first and second parts of the exam.

The exam in computer science lasts 235 minutes

Of these, 90 minutes are allotted for solving problems from the first part. On average, each task from the first part takes from 3 to 5 minutes. It takes 10 minutes to solve problem #23.

There are 145 minutes left to solve the tasks of the second part of the exam, while solving the last task No. 27 will take at least 55 minutes. These calculations were made by experts Federal Institute pedagogical measurements and are based on past exam results, so they should be taken seriously and used as a benchmark in the exam.

Programming languages - which one to choose

BASIC. it obsolete language, and although it is still studied in schools, there is no point in wasting time on mastering it.
School algorithmic programming language. It is designed specifically for early learning programming, convenient for mastering the initial algorithms, but practically does not contain depth, there is nowhere to develop in it.
Pascal. It is still one of the most common programming languages for teaching in schools and universities, but its capabilities are also very limited. Pascal is quite suitable as the language for writing the exam.
C++. Universal language, one of the most fast languages programming. It is difficult to learn from it, but in practical application its possibilities are very wide.
Python. It is easy to learn at an elementary level, the only thing required is knowledge of English language. At the same time, with an in-depth study, Python provides the programmer with no less opportunities than C ++. Having started learning Python at school, you will continue to use it in the future, you will not have to relearn another language in order to reach new horizons in programming. For passing the exam It is enough to know "Python" at a basic level.

Good to know

Works in computer science are evaluated by two experts. If the expert evaluation results differ by 1 point, the higher of the two points is assigned. If the discrepancy is 2 points or more, the work is rechecked by a third expert.
A useful site for preparing for the exam in computer science -

The total number of participants in the main period of the exam this year is more than 67 thousand people. This number has increased significantly compared to 2017, when 52.8 thousand people took the exam, and compared to 2016 (49.3 thousand people ), which corresponds to the trend towards the development of the digital sector of the economy in the country.

In 2018, compared to 2017, the share of unprepared exam participants slightly increased (by 1.54%) (up to 40 test points). The share of participants decreased by 2.9% from base level preparation (range from 40 to 60 t.b.). The 61-80tb group of test takers increased by 3.71%, partly due to a 2.57% decrease in the share of the 81-100tb test takers. Thus, the total share of participants who scored significant for competitive admission to institutions higher education scores (61-100 TB), increased by 1.05%, despite a decrease in the average test score from 59.2 in 2017 to 58.4 this year. Some increase in the proportion of participants who scored high (81-100) test scores is partly due to improved preparation of exam participants, partly to the stability of the examination model

More detailed analytics and teaching materials The USE 2018 is available at the link.

Our website contains about 3,000 assignments for preparing for the Unified State Examination in Informatics in 2018. Overall plan examination paper is presented below.

PLAN OF THE EXAMINATION WORK OF THE USE ON INFORMATICS 2019

Designation of the level of difficulty of the task: B - basic, P - advanced, C - high.

Content elements and activities to be checked	Task difficulty level	The maximum score for completing the task	Estimated time to complete the task (min.)
Exercise 1. Knowledge of number systems and binary representation of information in computer memory
Task 2. Ability to build truth tables and logic circuits
Task 3.
Task 4. Knowledge of the file system for organizing data or the technology of storing, searching and sorting information in databases
Task 5. Ability to encode and decode information
Task 6. Formal execution of the algorithm written in natural language or the ability to create linear algorithm for a formal executor with a limited set of commands
Task 7. Knowledge of information processing technology spreadsheets and data visualization methods using charts and graphs
Task 8. Knowledge of the basic constructions of the programming language, the concept of a variable, the assignment operator
Task 9. The ability to determine the information transfer rate for a given channel bandwidth, the amount of memory required to store sound and graphic information
Task 10. Knowledge of methods for measuring the amount of information
Task 11. Ability to execute recursive algorithm
Task 12. Knowledge basic principles organization and functioning of computer networks, network addressing
Task 13. The ability to calculate the information volume of the message
Task 14. The ability to execute an algorithm for a specific performer with a fixed set of commands
Task 15. Ability to represent and read data in different types of information models (diagrams, maps, tables, graphs and formulas)
Task 16. Knowledge of positional number systems
Task 17. Ability to search for information on the Internet
Task 18. Knowledge of the basic concepts and laws of mathematical logic
Task 19. Working with arrays (filling, reading, searching, sorting, mass operations, etc.)
Task 20. Analysis of an algorithm containing a loop and branching
Task 21. Ability to analyze a program using procedures and functions
Task 22. Ability to analyze the result of the execution of the algorithm
Task 23. Ability to build and transform logical expressions
Task 24 (C1). Ability to read a fragment of a program in a programming language and correct errors
Task 25 (C2). Ability to compose an algorithm and write it as a simple program (10–15 lines) in a programming language
Task 26 (C3). Ability to build a game tree according to a given algorithm and justify a winning strategy
Task 27 (C4). Ability to create own programs (30–50 lines) for solving problems of medium complexity

Correspondence between minimum primary points and minimal test scores 2019. Order on amendments to Appendix No. 1 to the order of the Federal Service for Supervision in Education and Science. .

OFFICIAL SCALE 2019

THRESHOLD SCORE
The order of Rosobrnadzor established minimal amount points, confirming the participants' mastery of the main general educational programs of the secondary (complete) general education in accordance with the requirements of the federal state educational standard secondary (complete) general education. THRESHOLD IN COMPUTER SCIENCE AND ICT: 6 primary points (40 test points).

EXAM FORMS
You can download high quality forms from

Single State exam in computer science consists of 27 tasks. Each task is devoted to one of the topics studied in the framework of the school curriculum. Computer science is a core subject, so only those students who need it in the future take it. Here you can find out how to solve USE assignments in computer science, as well as to study examples and solutions based on detailed tasks.

All USE tasks all tasks (107) USE task 1 (19) USE task 3 (2) USE task 4 (11) USE task 5 (10) USE task 6 (7) USE task 7 (3) USE task 9 (5) USE task 10 (7) USE task 11 (1) USE task 12 (3) USE task 13 (7) USE task 16 (19) USE task 17 (4) USE without number (9)

The Quadrator performer has two commands: add 3 and square

The performer Quadrator has two teams, which are assigned numbers: 1 - add 3; 2 - square it. The first of them increases the number on the screen by 3, the second raises it to the second power. The performer works only with natural numbers. Write an algorithm for obtaining number B from number A, containing no more than K commands. In the answer, write down only the numbers of the commands. If there is more than one such algorithm, write down any of them.

Vasya makes up words in which only letters occur

Vasya makes up N-letter words in which only letters A, B, C occur, and the letter A appears exactly 1 time. Each of the other valid letters can occur any number of times in the word, or not at all. A word is any valid sequence of letters, not necessarily meaningful. How many words are there that Vasya can write?

Igor makes a table of code words for message transmission

Igor makes a table of code words for message transmission, each message has its own code word. Igor uses N-letter words as code words, in which there are only letters A, B, C, and the letter A appears exactly 1 time. Each of the other valid letters may occur any number of times in the codeword, or not at all. How many different code words can Igor use?

The task is included in the exam in computer science for grade 11 at number 10.

Algorithm for calculating the value of the function F(n)

Algorithm for calculating the value of the function F(n), where n is natural number, is given by the following relations. What is the value of the function F(K)? Write down only a natural number in your answer.

The task is included in the exam in computer science for grade 11 at number 11.

How many seconds does it take for a modem to send messages

How many seconds does it take for a modem transmitting messages at a rate of N bps to transmit a color bitmap of size AxB pixels, provided that the color of each pixel is encoded in K bits? (Enter only the number on the form.)

The task is included in the exam in computer science for grade 11 at number 9.

The decryptor needs to recover the corrupted message fragment

The decryptor needs to restore the damaged fragment of the message, consisting of 4 characters. There is reliable information that no more than five letters were used (A, B, C, D, E), and one of the symbols is in the third place... One of the letters is in the fourth place... One of the letters is in the first place ... On the second - ... Additional information appeared that one of the four options is possible. Which?

The task is included in the exam in computer science for grade 11 at number 6.

The meteorological station monitors air humidity

The meteorological station monitors air humidity. The result of one measurement is an integer from 0 to 100 percent, which is written using the smallest possible number of bits. The station made N measurements. Determine the information volume of the observation results.

What will the formula look like after the cell is copied

The cell contains a formula. What will the formula look like when cell X is copied into cell Y? Note: The $ sign is used to denote absolute addressing.

The task is included in the exam in computer science for grade 11 at number 7.

Being in the root directory of a newly formatted drive

Being in the root directory of the newly formatted disk, the student created K directories. Then, in each of the created directories, he created another N directories. How many directories were on the disk, including the root?

The task is included in the exam in computer science for grade 11.

Four pieces of paper were found at the crime scene.

Four pieces of paper were found at the crime scene. The investigation found that fragments of one IP address were recorded on them. The forensics labeled these fragments as A, B, C, and D. Retrieve the IP address. In your response, provide a sequence of letters representing the fragments, in the order corresponding to the IP address.

Petya wrote down the IP address of the school server on a piece of paper

Petya wrote down the school server's IP address on a piece of paper and put it in his jacket pocket. Petya's mother accidentally washed the jacket along with the note. After washing, Petya found four scraps with fragments of the IP address in his pocket. These fragments are labeled A, B, C, and D. Restore the IP address. In your response, provide a sequence of letters representing the fragments, in the order corresponding to the IP address.

The task is included in the exam in computer science for grade 11 at number 12.

When registering in a computer system, each user is given a password.

When registering at computer system each user is given a password consisting of 15 characters and containing numbers and capital letters. Thus, K different characters are used. Each such password in a computer system is written in the minimum possible and the same integer number of bytes (in this case, character-by-character encoding is used and all characters are encoded in the same and minimum possible number of bits). Determine the amount of memory allocated by this system for storing N passwords.

The task is included in the exam in computer science for grade 11 at number 13.

In some country, the car number is made up of capital letters

In some country, a license plate of length K characters is made up of capital letters(using M different letters) and any decimal digits. Letters with numbers can follow in any order. Each such number computer program is written with the minimum possible and the same integer number of bytes (in this case, character-by-character encoding is used and all characters are encoded with the same and minimum possible number of bits). Determine the amount of memory allocated by this program for writing N numbers.