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tamnd's digital brain — notes, problems, research

43815 notes

CF 280C - Game on Tree

We are given a tree with root at vertex 1. A game is played on this rooted tree until every node disappears. At each move, one of the currently remaining vertices is chosen uniformly at random.

codeforcescompetitive-programmingimplementationmathprobabilitiestrees
Kvant Math Problem 1383

I cannot write a solution to Kvant problem M1383 because the problem statement itself is not present in your message.

kvantmathematicsolympiad
CF 280E - Sequence Transformation

We are given a sequence of numbers that is already sorted in non-decreasing order. We need to produce another sequence of the same length such that each consecutive difference lies within a specified range, and each element is between 1 and an upper bound q.

codeforcescompetitive-programmingbrute-forcedata-structuresdpimplementationmath
CF 280D - k-Maximum Subsequence Sum

We maintain an array that changes over time. There are two kinds of operations. One operation updates a single position. The other asks for the maximum total sum obtainable by selecting at most k pairwise disjoint subarrays inside a given interval [l, r].

codeforcescompetitive-programmingdata-structuresflowsgraphsimplementation
CF 280A - Rectangle Puzzle

We are given a rectangle centered at the origin with sides parallel to the coordinate axes, having width w along the x-axis and height h along the y-axis. Another rectangle of the same dimensions is rotated around the origin by an angle α (given in degrees).

codeforcescompetitive-programminggeometry
Kvant Math Problem 1382

Before I begin the full solution, I need the text of Kvant problem M1382.

kvantmathematicsolympiad
CF 279A - Point on Spiral

We are asked to count how many times a horse must turn when moving along a spiral from the origin to a target point $(x, y)$.

codeforcescompetitive-programmingbrute-forcegeometryimplementation
Kvant Math Problem 1381

I cannot write a solution to Kvant problem M1381 without the actual problem statement or the diagram.

kvantmathematicsolympiad
CF 279B - Books

We have a row of books, and the time needed to read each book is known. Valera may start from any position and then read consecutive books to the right. He cannot skip books, and he only starts a book if he has enough remaining time to finish it completely.

codeforcescompetitive-programmingbinary-searchbrute-forceimplementationtwo-pointers
Kvant Math Problem 1380

Consider the expression

kvantmathematicsolympiad
Kvant Math Problem 1379

I do not have access to the graphical version of Kvant problem M1379, and the textual statement is not included in your message.

kvantmathematicsolympiad
Kvant Math Problem 1378

I cannot write a rigorous solution to Kvant problem M1378 because the actual problem statement is not present in the conversation.

kvantmathematicsolympiad
Kvant Math Problem 1377

I can produce a full solution in your requested format, but I need the **text of Kvant problem M1377**.

kvantmathematicsolympiad
Kvant Math Problem 1376

I cannot write a valid solution to Kvant problem M1376 from the information provided, because the actual problem statement is missing.

kvantmathematicsolympiad
Kvant Math Problem 1375

I see that the problem statement for Kvant M1375 is not yet fully provided.

kvantmathematicsolympiad
Kvant Math Problem 1374

I cannot write a rigorous solution to Kvant problem M1374 without the actual problem statement or diagram.

kvantmathematicsolympiad
Kvant Math Problem 1373

Let the sphere have radius $R$, and let the given plane be $\pi$.

kvantmathematicsolympiad
Kvant Math Problem 1372

I can prepare a complete solution in that format, but I need the **text version of Kvant problem M1372** to proceed.

kvantmathematicsolympiad
Kvant Math Problem 1371

Place points $A$ and $B$ on a circle and pick a point $P$ on the smaller arc $AB$.

kvantmathematicsolympiad
Kvant Math Problem 1370

I do not have the statement of Kvant problem M1370.

kvantmathematicsolympiad
Kvant Math Problem 1369

I do not have the textual version of Kvant Problem M1369.

kvantmathematicsolympiad
Kvant Math Problem 1368

I can prepare the full solution in the requested format.

kvantmathematicsolympiad
Kvant Math Problem 1367

I see that the problem statement for Kvant M1367 has not been provided in text.

kvantmathematicsolympiad
Kvant Math Problem 1366

I cannot write a solution to Kvant problem M1366 because the actual problem statement is not present in your message.

kvantmathematicsolympiad
Kvant Math Problem 1365

I cannot write a solution to Kvant problem M1365 because the actual problem statement is not present in your message.

kvantmathematicsolympiad
Kvant Math Problem 1364

I do not have the textual version of Kvant problem M1364.

kvantmathematicsolympiad
Kvant Math Problem 1363

I do not have the statement of Kvant problem M1363, and the prompt indicates that only the graphical version is available.

kvantmathematicsolympiad
Kvant Math Problem 1362

The problem statement for Kvant M1362 is not included in your message, and the web-accessible archive currently only indicates that the textual version is still being prepared rather than providing th…

kvantmathematicsolympiad
Kvant Math Problem 1361

I can proceed, but I need the **text of problem M1361** from Kvant.

kvantmathematicsolympiad
Kvant Math Problem 1360

I cannot write a solution to Kvant problem M1360 because the actual problem statement is missing.

kvantmathematicsolympiad
CF 279E - Beautiful Decomposition

A beautiful number is any power of two with either sign. In other words, every summand must be one of $$pm 2^0, pm 2^1, pm 2^2,dots$$ We are given a positive integer $n$, but not in decimal form.

codeforcescompetitive-programmingdpgamesgreedynumber-theory
Kvant Math Problem 1359

I can proceed with that, but I need the **text of Kvant problem M1359** to write a complete solution.

kvantmathematicsolympiad
CF 279D - The Minimum Number of Variables

We are given a sequence of distinct positive integers. The sequence is not arbitrary, it must be generated step by step using a collection of variables. At the beginning every variable contains 0. The first value of the sequence is special.

codeforcescompetitive-programmingbitmasksdp
CF 279C - Ladder

We are given a one-dimensional array of integers and a list of queries, each specifying a contiguous subsegment of the array. For every query, we need to determine whether the subsegment forms a "ladder.

codeforcescompetitive-programmingdpimplementationtwo-pointers
Kvant Math Problem 1358

I can write the complete solution in the format you specify, but I need the text of Kvant problem M1358.

kvantmathematicsolympiad
CF 277A - Learning Languages

We are asked to ensure that every employee at BerCorp can communicate with every other employee, either directly through a shared language or indirectly via a chain of translators.

codeforcescompetitive-programmingdfs-and-similardsu
Kvant Math Problem 1357

I can follow that framework precisely.

kvantmathematicsolympiad
Kvant Math Problem 1354

I cannot write a rigorous solution to Kvant problem M1354 from the information provided, because the actual problem statement is missing and the published version is graphical only.

kvantmathematicsolympiad
Kvant Math Problem 1353

I can prepare the complete Kvant-style solution once you provide the full textual problem statement for M1353.

kvantmathematicsolympiad
Kvant Math Problem 1352

Consider the definition of "close" numbers.

kvantmathematicsolympiad
Kvant Math Problem 1351

Let the right angle of triangle $ABC$ be at $A$.

kvantmathematicsolympiad
Kvant Math Problem 1350

Let us understand exactly what is being counted.

kvantmathematicsolympiad
Kvant Math Problem 1349

Let $a_i$ be the number of counters in sector $i$, with indices taken modulo $n$.

kvantmathematicsolympiad
Kvant Math Problem 1348

I can provide a full solution in the structure you specified, but I need the **exact problem statement for Kvant M1348**.

kvantmathematicsolympiad
Kvant Math Problem 1347

Consider a smaller version of the problem to gain insight.

kvantmathematicsolympiad
Kvant Math Problem 1346

I cannot write a rigorous solution to problem M1346 without the actual problem statement or diagram.

kvantmathematicsolympiad
Kvant Math Problem 1345

Before I begin the full solution, I need to clarify the precise statement of Kvant problem M1345.

kvantmathematicsolympiad
Kvant Math Problem 1344

I notice that the actual textual statement of Kvant problem M1344 is not included.

kvantmathematicsolympiad
Kvant Math Problem 1343

I cannot write a rigorous solution to problem M1343 because the actual problem statement is not present in your message.

kvantmathematicsolympiad
Kvant Math Problem 1342

I need the full text of Kvant problem M1342 to write a complete, rigorous solution.

kvantmathematicsolympiad
Kvant Math Problem 1341

Denote by

kvantmathematicsolympiad
Kvant Math Problem 1340

I can start preparing the complete Kvant M1340 solution in your requested format.

kvantmathematicsolympiad
Kvant Math Problem 1339

I cannot write a solution to Kvant problem M1339 from the information provided, because the actual problem statement is missing.

kvantmathematicsolympiad
Kvant Math Problem 1338

I notice that the statement of Kvant problem M1338 has not been provided.

kvantmathematicsolympiad
Kvant Math Problem 1337

I can do that.

kvantmathematicsolympiad
Kvant Math Problem 1336

I cannot write a solution to Kvant problem M1336 because the actual problem statement is not present in your message.

kvantmathematicsolympiad
Kvant Math Problem 1335

Solution to Kvant math problem 1335.

kvantmathematicsolympiad
Kvant Math Problem 1334

I cannot write a rigorous solution to Kvant M1334 without the actual problem statement.

kvantmathematicsolympiad
Kvant Math Problem 1333

Before I begin, I need the text of Kvant problem M1333.

kvantmathematicsolympiad
Kvant Math Problem 1332

A regular tetrahedron has four triangular faces and six edges.

kvantmathematicsolympiad
Kvant Math Problem 1331

Consider a unit square $ABCD$ with points $K$, $M$, $N$, $L$ on sides $BC$, $CD$, $DA$, $AB$ respectively, such that lines $AK$, $BM$, $CN$, $DL$ create four corner triangles of areas $S_1$, $S_2$, $S…

kvantmathematicsolympiad
Kvant Math Problem 1330

I do not have the statement of Kvant problem M1330.

kvantmathematicsolympiad
Kvant Math Problem 1329

Solution to Kvant math problem 1329.

kvantmathematicsolympiad
Kvant Math Problem 1328

Before proceeding with a full solution, I need the full text of Kvant problem M1328 in order to construct the rigorous, step-by-step proof according to your specifications.

kvantmathematicsolympiad
Kvant Math Problem 1327

I can do that.

kvantmathematicsolympiad
Kvant Math Problem 1326

The recurrence can be rewritten in a much more suggestive form:

kvantmathematicsolympiad
CF 276C - Little Girl and Maximum Sum

We are given an array of numbers and a set of interval queries over positions in that array. Each query asks for the sum of elements in a contiguous segment. Before answering any queries, we are allowed to permute the array freely.

codeforcescompetitive-programmingdata-structuresgreedyimplementationsortings
Kvant Math Problem 1325

I cannot write a rigorous solution to Kvant problem M1325 because the actual problem statement is missing.

kvantmathematicsolympiad
CF 276B - Little Girl and Game

We are given a string of lowercase letters and two players who take turns removing a single character. A player wins immediately before their turn if the current letters can be rearranged into a palindrome.

codeforcescompetitive-programminggamesgreedy
Kvant Math Problem 1324

Before I start the solution, I need the full text of Kvant problem M1324.

kvantmathematicsolympiad
Kvant Math Problem 1323

I need the full text of Kvant problem M1323 in order to produce a complete, rigorous solution.

kvantmathematicsolympiad
CF 276E - Little Girl and Problem on Trees

We are given a tree where almost every node behaves like a point on a thin structure. Every node except node 1 has degree at most 2, which means the tree is essentially a collection of simple chains attached to a single branching root.

codeforcescompetitive-programmingdata-structuresgraphstrees
Kvant Math Problem 1322

I cannot write a solution to Kvant problem M1322 without the actual problem statement or a description of the diagram.

kvantmathematicsolympiad
CF 276D - Little Girl and Maximum XOR

We are asked to find the maximum XOR value of two integers within a given inclusive range $[l, r]$. More concretely, for all pairs $a$ and $b$ such that $l le a le b le r$, we want the largest result of $a oplus b$.

codeforcescompetitive-programmingbitmasksdpgreedyimplementationmath
Kvant Math Problem 1321

For small boards the bound looks plausible.

kvantmathematicsolympiad
CF 276A - Lunch Rush

We are given a list of restaurants, where each restaurant has two values: a baseline enjoyment score and the time required to eat there. The coach only allows a fixed lunch duration.

codeforcescompetitive-programmingimplementation
CF 274B - Zero Tree

The input describes a tree where every vertex holds an integer value. The only allowed operation is global but structurally restricted: you pick a connected region that must contain vertex 1, and then you add either +1 or -1 to every value in that region.

codeforcescompetitive-programmingdfs-and-similardpgreedytrees
Kvant Math Problem 1320

I can follow your structure exactly, but I need the full text of Kvant problem M1320 to write the solution.

kvantmathematicsolympiad
Kvant Math Problem 1319

Before I can write the complete solution, I need the full text of Kvant problem M1319.

kvantmathematicsolympiad
Kvant Math Problem 1318

I cannot write a rigorous solution to Kvant problem M1318 without the actual problem statement or the diagram.

kvantmathematicsolympiad
Kvant Math Problem 1317

Before I begin, I need the exact text of Kvant problem M1317 in order to produce a fully rigorous solution according to the framework you specified.

kvantmathematicsolympiad
CF 274A - k-Multiple Free Set

We are given a collection of distinct positive integers, and we want to select as many of them as possible while avoiding a specific type of forbidden relationship.

codeforcescompetitive-programmingbinary-searchgreedysortings
Kvant Math Problem 1316

I can prepare the full six-section solution, but I need the text of Kvant problem M1316.

kvantmathematicsolympiad
CF 274E - Mirror Room

We are asked to simulate a laser beam moving through a two-dimensional grid. Each cell in the grid is either empty or blocked. The beam starts from a specific empty cell and moves diagonally in one of four directions: north-east, north-west, south-east, or south-west.

codeforcescompetitive-programmingdata-structuresimplementation
Kvant Math Problem 1315

I can do that.

kvantmathematicsolympiad
CF 274D - Lovely Matrix

We are given a matrix with n rows and m columns. Each row originally was sorted in non-decreasing order, but now some entries have been erased (marked -1) and the columns may have been shuffled.

codeforcescompetitive-programmingdfs-and-similargraphsgreedysortings
Kvant Math Problem 1314

I need the full text of Kvant problem M1314 in order to write the solution.

kvantmathematicsolympiad
CF 274C - The Last Hole!

We are given several points on a plane, each representing the center of a circle. These circles begin to grow at the same time, with their radius increasing linearly over time. A hole is any connected white region that is completely enclosed by black circles.

codeforcescompetitive-programmingbrute-forcegeometry
Kvant Math Problem 1313

I can do that.

kvantmathematicsolympiad
CF 273D - Dima and Figure

We are given a grid of size n by m where each cell is initially white. Dima can paint any subset of cells black. A painting is considered one of Dima's favorite figures if three conditions are met: at least one cell is painted, all painted cells form a connected set (connected…

codeforcescompetitive-programmingdp
Kvant Math Problem 1312

I cannot write a rigorous solution to problem M1312 from the information provided, because the problem statement itself is missing.

kvantmathematicsolympiad
Kvant Math Problem 1311

Consider a triangle with integer side lengths $x$, $y$, $z$ and let the altitudes corresponding to these sides be $h_x$, $h_y$, $h_z$, where $h_x$ is the altitude to side $x$, $h_y$ to $y$, and $h_z$…

kvantmathematicsolympiad
Kvant Math Problem 1310

Solution to Kvant math problem 1310.

kvantmathematicsolympiad
CF 273E - Dima and Game

We are asked to construct sequences of intervals, each interval defined by two integers (l, r), such that the first player has a guaranteed winning strategy in a specific two-player game.

codeforcescompetitive-programmingdpgames
Kvant Math Problem 1309

I can do that.

kvantmathematicsolympiad
CF 272A - Dima and Friends

Dima and his friends are deciding who will clean the apartment using a counting game. Everyone, including Dima, shows a number of fingers between one and five. They then count around the circle starting from Dima, with the total count equal to the sum of all fingers shown.

codeforcescompetitive-programmingimplementationmath
Kvant Math Problem 1308

Please provide the text version of the Kvant M1308 problem so I can write the rigorous solution in the six-section format you requested.

kvantmathematicsolympiad
Kvant Math Problem 1307

Solution to Kvant math problem 1307.

kvantmathematicsolympiad
Kvant Math Problem 1306

I do not have the full text of Kvant Problem M1306 from your input.

kvantmathematicsolympiad
Kvant Math Problem 1305

I do not have the statement of Kvant problem M1305, and the prompt indicates that the textual version is not available here.

kvantmathematicsolympiad