brain

The problem statement for “Codeforces 104128F - Triangles” is not included in your message, so I don’t have the actual definitions of the input, output, or the task the solution is supposed to solve.

I can’t reliably write a correct editorial for this without the actual problem statement. “Codeforces 104128E - Color the Tree” isn’t identifiable from the title alone, and guessing would very likely produce the wrong model, wrong constraints, and therefore a misleading…

Let $G$ be the given FBDD with node set $V(G)$.

I can’t write a correct editorial yet because the actual problem statement for “Codeforces 104128D - Chat Program” is missing from your prompt.

I can’t reliably write a correct Codeforces editorial for “104128C - Fabulous Fungus Frenzy” because the actual problem statement, input format, and constraints are missing from your prompt.

I’m missing the actual problem statement for Codeforces 104128B - Ropeway, and without it I can’t produce a correct editorial.

The statement for Codeforces 104135I (“НОД и подмножества”) is not included in your message, so I don’t have enough information to reconstruct the task reliably.

I can’t write a correct editorial for this yet because the actual problem statement is missing from your prompt. Right now I only see the title “Сложная матрица” and no description of what the matrix operations or required output are.

Let $h{a,b}(x)=((ax+b)gg(n-l)) bmod 2^l$, with $ain A={amid 0<a<2^n, a text{odd}}$ and $bin B={bmid 0le b<2^{n-l}}$. For fixed sets $P$ and $Q$ of $n$-bit integers, define $$I={h{a,b}(p)mid pin P},qquad J={h{a,b}(q)mid qin Q}.$$ Let $ $$Pr[h{a,b}(x)=h{a,b}(y)]le 2^{-l}.

I can’t write a correct editorial for this yet because the actual problem statement is missing. Right now I only see the title “Codeforces 104135G - Задача о перестановках”, but no description of what is given, what needs to be computed, or the…

I can’t write a correct editorial yet because the actual statement of Codeforces 104135F - “Крош и интересные пары чисел” is not included in your prompt, and it is not available in a clean form from the metadata we currently have.

Let $B$ be the BDD of $f(x_1,\dots,x_n)$ with root node $r$.

The problem statement section is empty, so there is no way to reconstruct what “Крош и строка” is actually asking. Any attempt to write a full editorial without the task definition would be guesswork and would likely produce a completely incorrect solution.

We are given a sequence of numbers representing a row of elements, each element having two attributes: a value and a removal cost. The game allows us to repeatedly pick two adjacent elements and delete the smaller-valued one, paying its associated removal cost.

I can’t reliably write a correct editorial for Codeforces 104135D - “Дождь” without the actual problem statement. Right now I only have the title, but no description of what the input/output represents or what the task is asking.

The problem statement for Codeforces 104135A - “Крош и пароль” is missing from your prompt, so there’s no reliable way to reconstruct the solution or write a correct editorial without guessing.

We are given an undirected graph where each vertex is a named place inside a university building. Some of these places are special: the starting point is deansoffice, the destination is street, and there is exactly one additional mandatory place, the room where the student’s…

Let the BDD represent $f(x_1,\dots,x_n)$ with variable order $x_1 < x_2 < \cdots < x_n$.

I can’t reliably reconstruct Codeforces 104142J (“Плоские фигуры”) from the title alone, and writing a correct editorial without the actual statement would risk inventing constraints, rules, or even the task itself.

The problem statement is missing from your prompt, so there is no way to reconstruct the task, constraints, or intended solution for “Codeforces 104142I - WA 132”. An editorial depends entirely on knowing what the input represents and what needs to be computed.

I can’t write a correct editorial for this without the actual problem statement. Right now the only thing available is the title, but “Сбалансированные деревья” (Balanced Trees) could correspond to multiple different tasks, and the required data…

The problem statement is missing from your prompt (both the input and output sections are empty), so there isn’t enough information to write a correct Codeforces editorial.

I can’t write a correct editorial for this problem yet because the actual problem statement is missing from your message. “Codeforces 104142E - Квадраты” alone isn’t enough to reconstruct the task reliably.

I can’t write a correct Codeforces editorial for this problem yet because the actual problem statement is missing. Right now I only have the title “104142F - Забор”, but no description of what the input represents, what needs to be computed, or even the constraints.

The statement content is missing in the prompt, so there isn’t enough information to reconstruct Codeforces 104142D (Пляж) reliably.

I can write the full editorial in exactly that format, but I’m missing the actual problem statement for Codeforces 104142B - Шифр.

This problem strips away all structure and asks for a fixed output regardless of the input. You are given some input stream, which may contain anything, but none of it influences the required result. The task is simply to produce a single exact string as the program’s output.

I can’t write a correct editorial for this yet because the actual problem statement is missing. “Codeforces 104142C - Окружности” is a geometry problem (circles), but without the exact rules, input format, and required output, any solution would be guesswork.

Exercise 31 describes a generic BDD evaluation scheme in which a function is computed by replacing each internal decision node labeled by variable $x_j$ with an algebraic combination of the values of...

We are asked to construct a very structured tiling of an $n times n$ grid using exactly $n$ rectangular regions. Each region is filled with a single letter, so visually each rectangle becomes a monochromatic block in the grid.

We are given a queue of $n$ distinct integers representing a permutation. Each value is a ranking, and the goal is to transform the queue into increasing order so that the smallest rank ends up at the front and the largest at the back.

We are given a grid world where each cell is either normal ground, lava, or mud. Cindy starts at a fixed cell, initially facing south, and must reach a target cell.

We are given three distinct points in the plane with integer coordinates, and we are asked to reason about all possible ways to complete them into a parallelogram by choosing a fourth vertex.

Let $f(x_1,\dots,x_n)$ be represented by an ordered reduced BDD with root node $r$.

I can’t write a correct Codeforces-style editorial without the actual problem statement. “Codeforces 104146I - Image of the Artist as Filipino” is not available in the prompt, and I don’t have the input/output description, constraints, or even the core task (graph, DP…

I can’t reliably write a correct editorial for this yet because the actual problem content is missing. Right now the “Problem Statement / Input / Output” sections are empty, so there’s no way to know what Codeforces 104146H - Harvest Moon Rabbits is asking, what the…

I can’t reliably write a correct editorial for Codeforces 104146G - Good as Gold because the problem statement is missing from your prompt. Right now, I only see the template sections (Input/Output are empty), so any attempt to reconstruct the problem would be guesswork.

I can’t write a correct editorial for CF 104146F - Four Warning without the actual problem statement. Right now you’ve only provided the title and metadata, but the solution structure, key observations, and even what the input/output represent all depend entirely on the…

The problem statement section is empty, so there isn’t enough information to write a correct editorial for Codeforces 104146E.

I can’t reliably write a correct editorial for “Codeforces 104146D - Digital Style!” because the actual problem statement (inputs, outputs, and rules) is missing from your prompt.

We are given a visual construction problem: instead of computing a numeric answer, we must simulate and print how a three-strand braid evolves over time using ASCII art. At the start, there are three vertical strands, each labeled by a distinct character from a given string.

We are given a short string that represents a faded name tag. The original name is known to be exactly one of three fixed strings: Alice, Bob, or Cindy. However, the observed string may contain lowercase or uppercase letters, and some positions may be unreadable, shown as a dot.

I can’t write a correct editorial for “Codeforces 104146C - Codemas Carols” without the actual problem statement. Right now the input/output sections are empty, so anything I write would be guesswork and would likely invent the wrong problem entirely.

We are given a binary string and we are allowed to delete any number of characters from it, possibly all but at least one character must remain.

Each test case gives a collection of $N$ independent pairs. From the $i$-th pair you must choose exactly one value, either $Ai$ or $Bi$. After all choices are made, all selected values are XORed together to produce a single number, called the Salkan.

A binary decision diagram is thin if it contains exactly one branch node labeled $j$ for each $1 le j le n$. Denote by $Sn$ the number of Boolean functions on $(x1,dots,xn)$ whose reduced ordered BDD is thin. Let $vj$ denote the unique node labeled $j$.

We are simulating a process where a person receives multiple deliveries of milk over time. Each delivery arrives on a specific day with a given quantity. Milk is not permanent: every batch has a fixed freshness window, after which it becomes unusable and must be discarded.

The problem statement section is empty, so there’s no way to reconstruct the actual task reliably. For a Codeforces editorial, the difference between a graph problem, a data structure problem, or a combinatorics problem completely changes the approach, so guessing would…

Let the contribution of a minterm corresponding to an assignment $x_1 \ldots x_n$ be C(x_1,\ldots,x_n)=\prod_{i=1}^n (1-p_i)^{1-x_i}p_i^{x_i}.

I don’t have the actual problem statement for Codeforces 104147F - Nesr El Sieve, so I can’t safely reconstruct the solution or write a correct editorial yet.

I can’t reliably write a correct editorial for “Codeforces 104147D - Do and Tak Game” because the problem statement is missing from your prompt, and I don’t have enough information to reconstruct the rules, constraints, or required output.

I don’t have the actual statement for Codeforces 104147E - I am not done yet in your prompt, so I can’t reconstruct the problem, constraints, or intended solution without risking inventing details.

I don’t have the actual statement of Codeforces 104147C - Disney Land in the prompt, and I can’t reliably reconstruct it from the title alone without risking inventing details.

I can write the full editorial in the format you want, but I’m missing the actual problem statement for Codeforces 104147A - Round 1.

I can’t reliably write a correct editorial without the actual problem statement for Codeforces 104147B (“I’ll call him Hanya”).

I’m missing the actual problem statement, so I can’t safely reconstruct the intended solution or write a correct editorial for it.

We are dealing with a shop that sells multiple products, where each product type may have a required number of units that must be purchased.

The problem statement is missing from the prompt, so there is no reliable way to reconstruct what Codeforces 104148A (“Сколько чисел”) is asking.

I don’t have the actual statement for Codeforces 104148B “Уникальный комикс”, and without it I can’t reliably reconstruct the intended algorithm or constraints.

We maintain a sequence of colored marbles. Initially there is a fixed list of colors, and then we process a stream of operations. Each operation inserts a single marble at a specified position in the current sequence.

A binary decision diagram is thin if it contains exactly one branch node labeled $j$ for each $1 le j le n$. Denote by $Sn$ the number of Boolean functions on $(x1,dots,xn)$ whose reduced ordered BDD is thin. Let $vj$ denote the unique node labeled $j$.

We are asked to construct a configuration of $n$ circles in the plane such that the total number of distinct intersection points between circles is exactly $k$.

We are given a binary string that represents a long staircase. Each character corresponds to a step, and only the positions marked with 1 are broken and need to be fixed.

We are modeling an umbrella whose shape is determined by a central point at the top and eight identical rigid ribs of fixed length. Fabric is stretched between adjacent ribs, forming eight identical triangular panels arranged around the center.

Harry is trying to reach a desert center that is exactly $d$ days away if he walks alone. Every day consumes one unit of water per person.

We are given a tournament with n competitors, each representing a school champion. For every competitor, we already know their ranking in the first two events. A lower rank is better, and all ranks in each event form a permutation of 1 through n.

We are given a set of students and a list of friendships between them. Each friendship is undirected. The key twist is that a magical process will run: whenever student A is friends with B, and B is friends with C, the spell forces A and C to become friends as well.

We are trying to identify an unknown integer $x$ in the range from 1 to 100. The only way to gain information about $x$ is by asking queries: we choose an integer $y$ in the same range and receive one of four possible responses depending on the relationship between $y$ and $x$.

We are given a sequence of words that must be written on paper in lines. Each word has a length in characters, and if two words appear on the same line they must be separated by exactly one space.

We are given several cauldrons of potion. Each cauldron contains a known number of liters and each liter has a known concentration of an ingredient.

The dungeon is described as a system built from a few primitive corridors that are then combined repeatedly. Each primitive corridor connects an entrance to an exit and behaves like a single undirected passage from one endpoint to another.

We are given a set of n objects, each representing a chain link. Some pairs of links are already connected, forming an undirected simple graph.

Let $f$ be represented by a reduced ordered binary decision diagram, and let $F(p)$ denote the reliability polynomial under the specialization $p_1=\cdots=p_n=p$.

I can write the full editorial in exactly the format you want, but I don’t have the actual statement of Codeforces 104150D (“Преступная сеть”) available in this context, and I shouldn’t guess it because that would produce a misleading solution.

I can’t reliably write a correct editorial for this without the actual problem statement. “Codeforces 104150A - Допрос подозреваемых” (Interrogation of suspects) isn’t enough to reconstruct the task, and guessing would almost certainly produce a wrong…

I’m missing the actual problem statement for Codeforces 104150B (“Исследование улик”). Without knowing what the input represents or what is being computed, I can’t reliably reconstruct the intended solution, and anything I write would risk being incorrect…

I can’t reliably reconstruct Codeforces 104150C (“Зашифрованное сообщение”) from the identifier alone, and the problem statement isn’t included in your prompt.

I can’t reliably write a correct editorial for this problem yet because the actual problem statement is missing.

We are given a square-shaped robot with fixed side length k placed on a 2D plane. The robot starts at a known position and then moves in a sequence of straight-line segments.

I can’t reliably write a correct editorial for this problem yet because the statement is missing from your prompt.

I cannot reliably reconstruct the full official statement of “Codeforces 1041552 - Произведение Фибоначчи” from the title alone, and the exact input/output format is essential for a correct editorial.

We are given multiple queries, and each query is a string over the alphabet {a, b, c}. Two strings are considered equivalent if they “look the same” when you only observe how pairs of consecutive characters behave.

We are given a system of $n$ engines that all receive the same control parameter $x$, which we can think of as a global voltage. Each engine reacts to this voltage in a piecewise linear way. Every engine $i$ has a threshold $zi$.

I don’t have the actual statement for Codeforces 1041566 “Красивые последовательности” in the prompt, so I can’t reliably reconstruct the problem, constraints, or intended solution.

I can’t reliably write a correct Codeforces editorial without the actual problem statement for “1041567 - Камни”.

A quadratic curve describes how a drunk coworker walks across a rectangular office. At any horizontal position $x$, his position is $f(x)$, so his path is a parabola. He cannot see infinitely precisely.

Let $f(x_1,\ldots,x_n)$ be a Boolean function and let G(z)=\sum_{x_1=0}^1 \cdots \sum_{x_n=0}^1 z^{x_1+\cdots+x_n} f(x_1,\ldots,x_n) be its generating function as defined in the preceding exercise.

The building can be seen as a rooted structure where room numbers represent nodes in a very large implicit tree. Room 0 is the root. Every room belongs to a floor, and the structure alternates branching rules depending on whether the floor index is even or odd.

We are given a sequence of employees standing in a fixed order, where each employee has a known typing duration. There are M identical computers, and these computers act like parallel processors that continuously take the next available person in the queue.

We are given two large integers per test case, representing available counts of two complementary parts. From these counts, Thomas effectively produces a number of complete pairs equal to the greatest common divisor of the two values.

We are given a sequence of $N$ time slots. In each slot $i$, there are three employees, and each employee would contribute a known number of ideas if invited during that slot. However, Michael has two restrictions that interact in a nontrivial way.

We are given a target string consisting only of the characters T and C. We want to count how many different ways an employee can produce this exact string using a fixed set of stamps.

We are given a circular target on a 2D plane and a list of points representing where different employees threw an object. The task is to count how many of these thrown points land inside the circle or exactly on its boundary. Each throw is just a coordinate pair.

We are given a weekly supply limit, and Michael is allowed to make exactly one purchase. The restriction is that the quantity he buys must be a power of two. Among all valid purchase amounts that do not exceed the available supply, we need to choose the largest one.

We are given a collection of chocolates, each with a known amount of sugar. Thomas has a daily sugar limit and wants to eat as many whole chocolates as possible without the total sugar exceeding that limit.

We are given an undirected tree with $n$ nodes, representing office buildings connected by $n-1$ hallways. On this tree, there are $m$ ordered pairs of nodes, and each pair defines a journey that follows the unique simple path between its endpoints.

We are given a line of tiles, initially each tile has height 1. Over time, the heights only increase. Each operation selects a contiguous segment and adds the same value to every tile in that segment.

Let $H$ be an $m\times n$ parity-check matrix over $\mathbb{F}_2$, and let f(x)= [Hx=0], \qquad x=(x_1,\dots,x_n)^T.

We are given a quadratic curve that models a drunk coworker’s path across a rectangular room. At any horizontal position $x$, the coworker is located at height $f(x)$, where $f$ is a quadratic function.

We can think of the building as an infinite rooted structure starting from room 0. Each room generates new rooms in the level above it, but the branching factor depends on the parity of the room: even-indexed rooms expand into a rooms, and odd-indexed rooms expand into b rooms.