Kimy exam in computer science for a year. Collection of ideal social studies essays

FROM modern world technologies and realities of programming, development USE in Informatics has little in common. There are some basic points, but even if you understand tasks a little, this does not mean that you will eventually become a good developer. But there are a lot of areas where IT specialists are needed. You will not lose at all if you want to have a stable income above the average. In IT, you get it. Provided, of course, that you have the appropriate skills. And you can develop and grow here as much as you like, because the market is so huge that you can’t even imagine! And it is not limited only to our state. Work for any company from anywhere in the world! This is all very inspiring, so let the preparation for the exam in computer science be the first small step, after which years of self-development and improvement in this area will follow.

Structure

Part 1 contains 23 short answer tasks. This part contains tasks with a short answer, implying an independent formulation of a sequence of characters. Tasks check the material of all thematic blocks. 12 tasks belong to the basic level, 10 tasks to an increased level of complexity, 1 task to a high level of complexity.

Part 2 contains 4 tasks, the first of which is of an increased level of complexity, the remaining 3 tasks are of a high level of complexity. The tasks of this part involve writing a detailed answer in an arbitrary form.

3 hours 55 minutes (235 minutes) are allotted to complete the examination paper. It is recommended to take 1.5 hours (90 minutes) to complete the tasks of part 1. The rest of the time is recommended to be devoted to the tasks of part 2.

Explanations for grading assignments

The performance of each task of part 1 is estimated at 1 point. The task of part 1 is considered completed if the examiner gave the answer corresponding to the code of the correct answer. Completion of the tasks of part 2 is estimated from 0 to 4 points. The answers to the tasks of part 2 are checked and evaluated by experts. Maximum amount points that can be obtained for completing the tasks of part 2 - 12.

Many would not mind insuring themselves with ready-made answers to the USE-2017 in computer science. The exam is really not easy, you won’t be able to leave on intuition - you need to know. But do not rush to download answers from the first businessmen who come across the Web. First, let's figure out where the USE answers in computer science can come from; how realistic is it that anyone has them at all.

To whom and how do the USE answers get

There are three potential sources of prohibited information:

  1. hackers break into mail or other servers of the Ministry of Education and Science or FIPI;
  2. some of the employees of the Ministry and its departments violate the secret;
  3. On the day of the exam, teachers or students promptly complete assignments from KIMs officially printed in the Far East and send them to the western regions, with which the difference between them can reach 6-8 hours.

Logic dictates that the first two sources are the most expensive, because we are talking about exclusive information that a graduate can have in advance. The third source for the graduate is less expensive (and let's say in advance that it is completely useless).

What sources of USE-2017 answers in computer science can be trusted

From East to West

The trick with the time difference between different regions is no longer a trick, but rather stupidity on the part of some graduates and laziness on the part of scammers who could not come up with a more tempting argument. The fact is that KIMs are different everywhere. A large number of options have been developed, and if you don’t know which KIM options your region will get (and this is unknown to anyone except the elite), you don’t get answers, but a lottery with a very small chance of winning.

Of course, individual tasks may coincide, since they come from the same database, but it’s hardly worth spending time looking for answers and money to purchase them (although sometimes answers are offered for free, so to speak, from the Unified State Examination solidarity).

Hackers and corrupt officials

Of course, no one on the Web introduces himself: “Hello, I am a hacker (or a corrupt official). I'm ready to make you a unique selling proposition that you can't refuse."

However, you can meet the following "tender" story.

Eleventh-graders lived and lived in one school, and before they were all tired of preparing for exams, they decided to collect all the money together and buy USE answers through one person who has the necessary connections. With the world on a thread - bought. Yes, it got too expensive. They decided to win back their money, but at the same time help the rest of the students, and began to sell the purchased answers to others. “And how not to buy something,” people think, “after all, we believe our own, relatives, the same schoolchildren.”

Very similar to epic. But it most likely is. Fraudsters try to allegedly speak the language of "customers", attract them with a folding legend about the origin of the answers, and successfully cash in on the fact that it is easy to disappear on the Internet at the right time.

Add to this observation that none of the previous exams that have already taken place this year have revealed information leaks. Neither in the media nor on the Internet, no one en masse writes that the answers that were posted on the Web agreed with the tasks in the exam. Will this series of Rosobrnadzor's successes be interrupted in computer science? Doubtful.

Output

There is only one conclusion: you cannot trust any sources of USE answers. There is more swindle in this matter than real help.

How to pass the USE-2017 in informatics without answers

In computer science KIMs there will be no very easy questions like “Define the binary number system”, etc. All 23 closed and 4 open tasks are aimed at testing your ability to analyze and apply knowledge. Without at least mediocre preparation for the exam, be prepared to retake. Alas, this year it will not work to retake the subject of choice and you will have to wait for the next year. On the other hand, you will have a whole year to study the subject perfectly and at a measured pace. And those who, because of the failure to pass computer science this year, are threatened by the army, will find benefit at least in the fact that after the service they will be able to enter the university on preferential terms.

If your interest in answers is dictated by simple self-doubt and the desire to insure, then everything is much simpler. You just don't need answers. You just need to repeat the basic things at night, sleep well and come to the exam with a fighting spirit.

Good luck to everyone on the exam!

The lesson is devoted to how to solve the 3rd task of the exam in computer science


The 3rd topic is characterized as tasks of a basic level of complexity, the execution time is about 3 minutes, the maximum score is 1

* Some page images are taken from K. Polyakov's presentation materials

Structuring information and information models

Let us briefly consider the 3 USE assignments concepts.

Structuring information- this is the establishment of the main elements in information messages and the establishment of links between them.

Structuring is done with purpose facilitate the perception and search for information.

Structuring is possible using the following structures (information models):

  • lots of:
  • enumeration of elements collected by characteristic;

    Vasya, Petya, Kolya 1, 17, 22, 55

    In a set, the ordering of elements is not necessary, i.e. the order is not important.

  • linear list
  • The order of the elements is important.

    The tables highlight objects(separate table entries) and properties(column names or row names):

  • tree or hierarchy of objects
  • Consider family relationships in the tree:

  • "Sons" A: b, c.
  • "Parent" B: A.
  • "Descendants" A: B, C, D, E, F, G.
  • "Ancestors" F: A, C.
  • Root– node without ancestors (A).
    Sheet– node without descendants (D, E, F, G).
    Height- the greatest distance from the root to the leaf (number of levels).

  • file system (hierarchy)
  • Let's say the computer's hard drive has the following folders (directories) with files:

    Let's get a tree:

  • graphs
  • Sometimes it is very difficult to structure information in the described structures because of the complex "relationships" between objects. Then you can use graphs:

    is a set of vertices and connections between them, called edges:

    Graph showing roads between villages

  • matrix and adjacency list
  • is a graph with a path between any vertices.


    Wood is a connected graph without cycles (closed sections).

    Tree is a connected graph without cycles

  • weighted graphs and weight matrix
  • Weighted graphs have an "edge weight":

    From the weighted graphs, a weight matrix is ​​obtained, the inverse transformation is also possible.

    Finding the shortest path (brute force)

    Finding the shortest path between points A and D

    • In the USE tasks of this topic, two information models are most often used - tables and diagrams.
    • Information in the table is built according to the following rules: at the intersection of a row and a column, there is information characterizing the combination of this row and column.
    • On the diagram information is built according to the following rule: if there is a connection between the objects of the scheme, then it is displayed by a line connecting the names of these objects on the diagram.

    Solving tasks 3 USE in Informatics

    3_3: Solution 3 of the USE task in informatics (control version No. 1 of the 2018 examination paper, S.S. Krylov, D.M. Ushakov):

    Between settlements A, B, C, D, E, F roads were built, the length of which is given in the table (if the cell is empty, there is no road).

    A B C D E F
    A 7 3
    B 7 2 4 1
    C 3 2 7 5 9
    D 4 7 2 3
    E 1 5 2 7
    F 9 3 7

    Determine the length of the shortest path between points A And F .


    ✍ Solution:

    Result: 11

    Video analysis of the task:

    3_4:Solution 3 of the USE task in informatics (variant 11 of the GVE in informatics 2018):

    Roads were built between settlements A, B, C, D, E, F, the length of which is shown in the table. The absence of a number in the table means that there is no direct road between the points.

    A B C D E F
    A 3 7 6
    B 3 4 4
    C 7 5 9
    D 4 5 5
    E 6 4 8
    F 9 5 8

    Determine the length the shortest way between points A And F provided that it is possible to move only on the roads indicated in the table.


    ✍ Solution:

    Result: 12

    3_5: Solution 2* of the task of the Unified State Examination in Informatics 2018, option 10 (FIPI, “Unified State Exam Informatics and ICT, typical exam options 2018”, S.S. Krylov, T.E. Churkina):

    Between settlements A, B, C, D, E, F, Z one-way roads were built. The table shows the length of each road (the absence of a number in the table means that there is no direct road between the points).

    A B C D E F Z
    A 3 5 14
    B 2 8
    C 2 7
    D 1 4 4
    E 1 5
    F 12 1 9
    Z

    How many such routes are there? A in Z, which go through five or more settlements? Items A And Z take into account when calculating. You cannot go through the same point twice.

    * in the new textbooks, tasks 2 and 3 have been swapped: now 2 - Finding the shortest path, and 3 - Algebra of logic


    ✍ Solution:

    Result: 6

    3_2: 3 task. Demo version of the Unified State Examination 2018 Informatics (FIPI):

    In the figure, the road map of the N-sky district is shown as a graph, the table contains information about the length of each of these roads (in kilometers).


    Since the table and the diagram were drawn independently of each other, the numbering of settlements in the table is in no way connected with the letter designations on the graph. Determine the length of the road from the point BUT to paragraph G. In your answer, write down the whole number - as it is indicated in the table.


    ✍ Solution:
    • Let's count how many edges each vertex has:
    A -> 3 (C D E) B -> 1 (C) C -> 4 (A B D F) D -> 4 (A C D K) E -> 2 (A D) F -> 1 (C ) K -> 1 (G)
  • Three edges have only one vertex - BUT, so only A can match P3.
  • The vertex also has a unique value for the number of edges D, are two edges. Top table D will match P4.
  • Peaks G And IN have by 4 ribs. Consider a matrix, in which 4 numbers correspond to points P2 And P5.
  • With paragraph D only top crosses G(G -> 4 (A B D K)). In the weight matrix with vertex D stopped P5. Means top G corresponds P5.
  • IN P5 at the intersection with P3 is the number 6 .
  • Result: 6

    For a detailed solution of this 3 task from the USE demo version of 2018, see the video:

    3_1: Unified State Examination in Informatics 2017, assignment from the collection of Ushakov D.M, 1st option:

    In the figure, the road map of the N-sky district is shown as a graph, the table contains information about the lengths of these roads (in kilometers).



    Since the table and the scheme were drawn independently of each other, the numbering of settlements in the table is in no way connected with the letter designations on the graph.
    Determine the length of the road from the point D to paragraph TO. In your answer, write down the whole number - as it is indicated in the table.


    ✍ Solution:
    • Consider a graph and count the number of edges from each vertex:
    A -\u003e 2 ribs (D, C) C -\u003e 4 ribs (A, D, K, D) D -\u003e 4 ribs (A, C, K, E) B -\u003e 2 ribs (D, K) K - > 5 ribs (B, D, C, D, E) F -\u003e 2 ribs (K, D) D -> 3 ribs (B, K, E)
  • We selected vertices, with a unique number of edges: 3 edges corresponds to a vertex only D, and 5 edges correspond only to the vertex TO.
  • Consider the table and find those rows or columns in which there are 5 values ​​and 3 values: This P2 And P4.
  • We get P2 corresponds D, but P4 corresponds TO. At the intersection is a number 20 .
  • Result: 20

    In addition, you can watch the video of the solution to this USE task in computer science:

    3_6: Analysis of 3 tasks of the Unified State Examination option No. 1, 2019 Informatics and ICT Typical exam options (10 options), S.S. Krylov, T.E. Churkina:

    The figure shows a road map of the N-sky district, in the table an asterisk indicates the presence of a road from one settlement to another, the absence of an asterisk means that there is no such road. Each settlement on the diagram corresponds to its number in the table, but it is not known which number.

    1 2 3 4 5 6 7 8
    1 * * *
    2 * * *
    3 * *
    4 * * * * * *
    5 * * *
    6 * * *
    7 * * *
    8 * * *

    Determine which settlement numbers in the table can correspond to settlements D And E on the diagram? In your answer, write down these two numbers in ascending order without spaces or punctuation marks.


    ✍ Solution:
    • First, let's find unique vertices - which have a unique number of edges: this A(2 ribs) and H(6 ribs). In the table, they correspond to numbers 3 and 4:
    • 1 2 A H 5 6 7 8
      1 * * *
      2 * * *
      A * *
      H * * * * * *
      5 * * *
      6 * * *
      7 * * *
      8 * * *
    • According to the scheme, we find that the adjacent vertices for A are B And G. In the table, we determine the numbers corresponding to them - 1 and 2. Since they do not interest us according to the assignment, we denote them together:
    • B,G B,G A H 5 6 7 8
      B,G * * *
      B,G * * *
      A * *
      H * * * * * *
      5 * * *
      6 * * *
      7 * * *
      8 * * *
    • Both vertices B and G are adjacent to the already known A and H and, in addition, the vertices F And C. According to the first column or the first row, we find that F or C will correspond to the number 7, and according to the second line - the number 8. Let's designate them in the table:
    • B,G B,G A H 5 6 F,C F,C
      B,G * * *
      B,G * * *
      A * *
      H * * * * * *
      5 * * *
      6 * * *
      F,C * * *
      F,C * * *
    • As a result, we get that the desired vertices - D And E- numbers match 5 And 6 . Since it does not matter which digit this or that vertex should correspond to, then in the answer we simply write these numbers in ascending order.

    Hello, dear readers of the blog site. We continue to look, decide, remember what has already been forgotten. Today, on the queue of the Unified State Examination in Informatics 2017, I will try to sort out the assignments as much as possible, indicate what you need to know to successfully pass the Unified State Examination, and also share my impressions of the assignments. I remind you that the exam in mathematics and the level, and have already been sorted out, you can read about the demo versions of these subjects at the links.

    I passed the exam a long time ago, there were few such tasks at the university, and far from all, so I ask you to understand and forgive me if you disagree with my assessments of complexity or necessity. But nevertheless, I will write an article, I hope it will be useful to someone, and someone will express their opinion in the comments.

    USE in Informatics 2017, what you need to know

    Generally speaking, judging by the demo version of the Unified State Examination in Informatics 2017, you need to know a lot, I hope the graduates know all this and it will not be somehow unusual for them to see such tasks.

    You need to know the binary number system

    Again, I won’t tie the list of necessary knowledge to task numbers, I’ll just give it as a list, so let’s go, I’ll try as it gets more complicated:

    • Work with spreadsheets. Anyone who has used Excel will do this task without any problems.
    • Know what number systems are. At least binary, octal, decimal and hexadecimal, although there may be number systems with any base, for example 3. And not only know, but also be able to translate from one number system to another. Moreover, to save time, it is better to understand which number system it will be easier and faster to translate into. For example, look at the first task, which contains a demo version of the Unified State Examination in Informatics 2017, there you can save a lot of time if you convert from binary to hexadecimal, and not convert everything to decimal.
    • Know logical functions, truth tables for them and be able to work with truth tables for expressions consisting of several logical functions.
    • Be able to work with graphs and tables. Moreover, sometimes they can be connected and it is necessary to establish the relationship between them.
    • To be able to represent textual information in the form of discrete, that is, digital, and to know the units of measurement of information.
    • To some extent, a continuation of the previous subparagraph. The ability to estimate the amount of memory needed to store one or another type of information (text, graphics, video, etc.)
    • Know at least one programming language and be able to use it, how to write programs (more on that later), and understand what has already been compiled.
    • Knowledge of computer networks, in particular, in the demo version there was a question about the TCP / IP protocol stack, perhaps there will be something else on the exam.
    • Understand code written not in a programming language, but in Russian, if it’s not clear what I mean, see task 14 from the USE demo version.
    • Be able to write programs in one of the programming languages ​​according to the task. And also understand someone else's code and find errors that were made when writing programs.

    USE in Informatics 2017, impressions

    After 5 years of studying computer science and programming at the university, I can’t say that the tasks seemed so easy. No, of course, everything is solvable, but you also need to know quite a lot. So the USE in Informatics 2017 is not very simple, it will be quite difficult to pass.

    Important! If you cannot solve any task from part 2 given in the USE demo version, and do not even try to figure it out, being sure that you will have enough points for admission. even NOT go to university, to a specialty related to computer science and programming. Believe me, you can and will learn to program, but you will spend miles of nerves at the same time. So think very carefully whether you need it, especially since there is a possibility that you will never learn to program. And after thinking, it's better to give up programming anyway.