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apps_data_2300
Snuke has a rooted tree with N+1 vertices. The vertices are numbered 0 through N, and Vertex 0 is the root of the tree. The parent of Vertex i (1 \leq i \leq N) is Vertex p_i. Besides this tree, Snuke also has an box which is initially empty and many marbles, and playing with them. The play begins with placing one marb...
apps_data_2301
You are in charge of controlling a dam. The dam can store at most L liters of water. Initially, the dam is empty. Some amount of water flows into the dam every morning, and any amount of water may be discharged every night, but this amount needs to be set so that no water overflows the dam the next morning. It is known...
apps_data_2302
Alice lives on a line. Today, she will travel to some place in a mysterious vehicle. Initially, the distance between Alice and her destination is D. When she input a number x to the vehicle, it will travel in the direction of the destination by a distance of x if this move would shorten the distance between the vehicle...
apps_data_2303
Snuke's town has a subway system, consisting of N stations and M railway lines. The stations are numbered 1 through N. Each line is operated by a company. Each company has an identification number. The i-th ( 1 \leq i \leq M ) line connects station p_i and q_i bidirectionally. There is no intermediate station. This lin...
apps_data_2304
Sig has built his own keyboard. Designed for ultimate simplicity, this keyboard only has 3 keys on it: the 0 key, the 1 key and the backspace key. To begin with, he is using a plain text editor with this keyboard. This editor always displays one string (possibly empty). Just after the editor is launched, this string is...
apps_data_2305
Takahashi has an ability to generate a tree using a permutation (p_1,p_2,...,p_n) of (1,2,...,n), in the following process: First, prepare Vertex 1, Vertex 2, ..., Vertex N. For each i=1,2,...,n, perform the following operation: - If p_i = 1, do nothing. - If p_i \neq 1, let j' be the largest j such that p_j < p_i. S...
apps_data_2306
There are N pinholes on the xy-plane. The i-th pinhole is located at (x_i,y_i). We will denote the Manhattan distance between the i-th and j-th pinholes as d(i,j)(=|x_i-x_j|+|y_i-y_j|). You have a peculiar pair of compasses, called Manhattan Compass. This instrument always points at two of the pinholes. The two legs of...
apps_data_2307
There are N towns on a line running east-west. The towns are numbered 1 through N, in order from west to east. Each point on the line has a one-dimensional coordinate, and a point that is farther east has a greater coordinate value. The coordinate of town i is X_i. You are now at town 1, and you want to visit all the o...
apps_data_2308
You are given $n$ arrays that can have different sizes. You also have a table with $w$ columns and $n$ rows. The $i$-th array is placed horizontally in the $i$-th row. You can slide each array within its row as long as it occupies several consecutive cells and lies completely inside the table. You need to find the max...
apps_data_2309
Masha and Grisha like studying sets of positive integers. One day Grisha has written a set A containing n different integers a_{i} on a blackboard. Now he asks Masha to create a set B containing n different integers b_{j} such that all n^2 integers that can be obtained by summing up a_{i} and b_{j} for all possible pa...
apps_data_2310
Important: All possible tests are in the pretest, so you shouldn't hack on this problem. So, if you passed pretests, you will also pass the system test. You are an adventurer currently journeying inside an evil temple. After defeating a couple of weak monsters, you arrived at a square room consisting of tiles forming ...
apps_data_2311
Let us define two functions f and g on positive integer numbers. $f(n) = \text{product of non-zero digits of} n$ $g(n) = \left\{\begin{array}{ll}{n} & {\text{if} n < 10} \\{g(f(n))} & {\text{otherwise}} \end{array} \right.$ You need to process Q queries. In each query, you will be given three integers l, r and k. Y...
apps_data_2312
Toad Pimple has an array of integers $a_1, a_2, \ldots, a_n$. We say that $y$ is reachable from $x$ if $x<y$ and there exists an integer array $p$ such that $x = p_1 < p_2 < \ldots < p_k=y$, and $a_{p_i}\, \&\, a_{p_{i+1}} > 0$ for all integers $i$ such that $1 \leq i < k$. Here $\&$ denotes the bitwise AND operation...
apps_data_2313
Kalila and Dimna are two jackals living in a huge jungle. One day they decided to join a logging factory in order to make money. The manager of logging factory wants them to go to the jungle and cut n trees with heights a_1, a_2, ..., a_{n}. They bought a chain saw from a shop. Each time they use the chain saw on the...
apps_data_2314
For an array $b$ of length $m$ we define the function $f$ as $ f(b) = \begin{cases} b[1] & \quad \text{if } m = 1 \\ f(b[1] \oplus b[2],b[2] \oplus b[3],\dots,b[m-1] \oplus b[m]) & \quad \text{otherwise,} \end{cases} $ where $\oplus$ is bitwise exclusive OR. For example, $f(1,2,4,8)=f(1\oplus2,2\oplus4,4\oplus8)=f(...
apps_data_2315
Vasya has written some permutation $p_1, p_2, \ldots, p_n$ of integers from $1$ to $n$, so for all $1 \leq i \leq n$ it is true that $1 \leq p_i \leq n$ and all $p_1, p_2, \ldots, p_n$ are different. After that he wrote $n$ numbers $next_1, next_2, \ldots, next_n$. The number $next_i$ is equal to the minimal index $i <...
apps_data_2316
Koa the Koala and her best friend want to play a game. The game starts with an array $a$ of length $n$ consisting of non-negative integers. Koa and her best friend move in turns and each have initially a score equal to $0$. Koa starts. Let's describe a move in the game: During his move, a player chooses any element ...
apps_data_2317
You have an array $a$ of length $n$. For every positive integer $x$ you are going to perform the following operation during the $x$-th second: Select some distinct indices $i_{1}, i_{2}, \ldots, i_{k}$ which are between $1$ and $n$ inclusive, and add $2^{x-1}$ to each corresponding position of $a$. Formally, $a_{i_{...
apps_data_2318
During the last Sereja's Codesecrof round the server crashed many times, so the round was decided to be made unrated for some participants. Let's assume that n people took part in the contest. Let's assume that the participant who got the first place has rating a_1, the second place participant has rating a_2, ..., t...
apps_data_2319
We start with a permutation $a_1, a_2, \ldots, a_n$ and with an empty array $b$. We apply the following operation $k$ times. On the $i$-th iteration, we select an index $t_i$ ($1 \le t_i \le n-i+1$), remove $a_{t_i}$ from the array, and append one of the numbers $a_{t_i-1}$ or $a_{t_i+1}$ (if $t_i-1$ or $t_i+1$ are wi...
apps_data_2320
Leha like all kinds of strange things. Recently he liked the function F(n, k). Consider all possible k-element subsets of the set [1, 2, ..., n]. For subset find minimal element in it. F(n, k) — mathematical expectation of the minimal element among all k-element subsets. But only function does not interest him. He wan...
apps_data_2321
Roger is a robot. He has an arm that is a series of n segments connected to each other. The endpoints of the i-th segment are initially located at points (i - 1, 0) and (i, 0). The endpoint at (i - 1, 0) is colored red and the endpoint at (i, 0) is colored blue for all segments. Thus, the blue endpoint of the i-th segm...
apps_data_2322
You are working for the Gryzzl company, headquartered in Pawnee, Indiana. The new national park has been opened near Pawnee recently and you are to implement a geolocation system, so people won't get lost. The concept you developed is innovative and minimalistic. There will be $n$ antennas located somewhere in the par...
apps_data_2323
There are N barbecue restaurants along a street. The restaurants are numbered 1 through N from west to east, and the distance between restaurant i and restaurant i+1 is A_i. Joisino has M tickets, numbered 1 through M. Every barbecue restaurant offers barbecue meals in exchange for these tickets. Restaurant i offers a ...
apps_data_2324
Fennec and Snuke are playing a board game. On the board, there are N cells numbered 1 through N, and N-1 roads, each connecting two cells. Cell a_i is adjacent to Cell b_i through the i-th road. Every cell can be reached from every other cell by repeatedly traveling to an adjacent cell. In terms of graph theory, the gr...
apps_data_2325
Let us consider the following operations on a string consisting of A and B: - Select a character in a string. If it is A, replace it with BB. If it is B, replace with AA. - Select a substring that is equal to either AAA or BBB, and delete it from the string. For example, if the first operation is performed on ABA and...
apps_data_2326
Snuke loves constructing integer sequences. There are N piles of stones, numbered 1 through N. The pile numbered i consists of a_i stones. Snuke will construct an integer sequence s of length Σa_i, as follows: - Among the piles with the largest number of stones remaining, let x be the index of the pile with the smalle...
apps_data_2327
Snuke has decided to play a game, where the player runs a railway company. There are M+1 stations on Snuke Line, numbered 0 through M. A train on Snuke Line stops at station 0 and every d-th station thereafter, where d is a predetermined constant for each train. For example, if d = 3, the train stops at station 0, 3, 6...
apps_data_2328
When Misha hits his favorite gym, he comes across an interesting problem with the barbell. In the gym, someone always leaves the weight plates in the strangest places you can imagine and sometime it's difficult to equip the barbell the way you want. Let's imagine that you have N weight plates placed in any order (remem...
apps_data_2329
You are given an array A, consisting of N integers and an array B, consisting of M integers. The subsequence of A is the array that can be obtained by picking the elements at the arbitrary sorted set of positions from A. Your task is to count the number of such subsequences C of A that: - C contains exactly M elements...
apps_data_2330
You are given a string s of length n. Does a tree with n vertices that satisfies the following conditions exist? - The vertices are numbered 1,2,..., n. - The edges are numbered 1,2,..., n-1, and Edge i connects Vertex u_i and v_i. - If the i-th character in s is 1, we can have a connected component of size i by rem...
apps_data_2331
There is an undirected tree of $n$ vertices, connected by $n-1$ bidirectional edges. There is also a snake stuck inside of this tree. Its head is at vertex $a$ and its tail is at vertex $b$. The snake's body occupies all vertices on the unique simple path between $a$ and $b$. The snake wants to know if it can reverse ...
apps_data_2332
There are $n$ cities in Berland and some pairs of them are connected by two-way roads. It is guaranteed that you can pass from any city to any other, moving along the roads. Cities are numerated from $1$ to $n$. Two fairs are currently taking place in Berland — they are held in two different cities $a$ and $b$ ($1 \le...
apps_data_2333
Consider the infinite sequence $s$ of positive integers, created by repeating the following steps: Find the lexicographically smallest triple of positive integers $(a, b, c)$ such that $a \oplus b \oplus c = 0$, where $\oplus$ denotes the bitwise XOR operation. $a$, $b$, $c$ are not in $s$. Here triple of intege...
apps_data_2334
Zookeeper is playing a game. In this game, Zookeeper must use bombs to bomb a string that consists of letters 'A' and 'B'. He can use bombs to bomb a substring which is either "AB" or "BB". When he bombs such a substring, the substring gets deleted from the string and the remaining parts of the string get concatenated....
apps_data_2335
Denis was very sad after Nastya rejected him. So he decided to walk through the gateways to have some fun. And luck smiled at him! When he entered the first courtyard, he met a strange man who was selling something. Denis bought a mysterious item and it was... Random permutation generator! Denis could not believed hi...
apps_data_2336
Petr likes to come up with problems about randomly generated data. This time problem is about random permutation. He decided to generate a random permutation this way: he takes identity permutation of numbers from $1$ to $n$ and then $3n$ times takes a random pair of different elements and swaps them. Alex envies Petr ...
apps_data_2337
So the Beautiful Regional Contest (BeRC) has come to an end! $n$ students took part in the contest. The final standings are already known: the participant in the $i$-th place solved $p_i$ problems. Since the participants are primarily sorted by the number of solved problems, then $p_1 \ge p_2 \ge \dots \ge p_n$. Help ...
apps_data_2338
This is the hard version of the problem. The difference between the versions is the constraint on $n$ and the required number of operations. You can make hacks only if all versions of the problem are solved. There are two binary strings $a$ and $b$ of length $n$ (a binary string is a string consisting of symbols $0$ a...
apps_data_2339
This is the easy version of the problem. The difference between the versions is the constraint on $n$ and the required number of operations. You can make hacks only if all versions of the problem are solved. There are two binary strings $a$ and $b$ of length $n$ (a binary string is a string consisting of symbols $0$ a...
apps_data_2340
Let $a$ and $b$ be two arrays of lengths $n$ and $m$, respectively, with no elements in common. We can define a new array $\mathrm{merge}(a,b)$ of length $n+m$ recursively as follows: If one of the arrays is empty, the result is the other array. That is, $\mathrm{merge}(\emptyset,b)=b$ and $\mathrm{merge}(a,\emptyset)...
apps_data_2341
You and your $n - 1$ friends have found an array of integers $a_1, a_2, \dots, a_n$. You have decided to share it in the following way: All $n$ of you stand in a line in a particular order. Each minute, the person at the front of the line chooses either the first or the last element of the array, removes it, and keeps ...
apps_data_2342
You are given an array $a$ of $n$ positive integers. You can use the following operation as many times as you like: select any integer $1 \le k \le n$ and do one of two things: decrement by one $k$ of the first elements of the array. decrement by one $k$ of the last elements of the array. For example, if $n=5$ an...
apps_data_2343
Dreamoon likes sequences very much. So he created a problem about the sequence that you can't find in OEIS: You are given two integers $d, m$, find the number of arrays $a$, satisfying the following constraints: The length of $a$ is $n$, $n \ge 1$ $1 \le a_1 < a_2 < \dots < a_n \le d$ Define an array $b$ of length...
apps_data_2344
You are given a graph with $3 \cdot n$ vertices and $m$ edges. You are to find a matching of $n$ edges, or an independent set of $n$ vertices. A set of edges is called a matching if no two edges share an endpoint. A set of vertices is called an independent set if no two vertices are connected with an edge. -----Inp...
apps_data_2345
It is Borya's eleventh birthday, and he has got a great present: n cards with numbers. The i-th card has the number a_{i} written on it. Borya wants to put his cards in a row to get one greater number. For example, if Borya has cards with numbers 1, 31, and 12, and he puts them in a row in this order, he would get a nu...
apps_data_2346
The USA Construction Operation (USACO) recently ordered Farmer John to arrange a row of $n$ haybale piles on the farm. The $i$-th pile contains $a_i$ haybales. However, Farmer John has just left for vacation, leaving Bessie all on her own. Every day, Bessie the naughty cow can choose to move one haybale in any pile t...
apps_data_2347
A bitstring is a string consisting only of the characters 0 and 1. A bitstring is called $k$-balanced if every substring of size $k$ of this bitstring has an equal amount of 0 and 1 characters ($\frac{k}{2}$ of each). You are given an integer $k$ and a string $s$ which is composed only of characters 0, 1, and ?. You n...
apps_data_2348
N hotels are located on a straight line. The coordinate of the i-th hotel (1 \leq i \leq N) is x_i. Tak the traveler has the following two personal principles: - He never travels a distance of more than L in a single day. - He never sleeps in the open. That is, he must stay at a hotel at the end of a day. You are giv...
apps_data_2349
The Chef has one long loaf of bread of length 1. He wants to cut it into as many little loaves as he can. But he wants to adhere to the following rule: At any moment, the length of the longest loaf which he possesses may not be larger than the length of shortest one, times some constant factor. Every time, he is only a...
apps_data_2350
A hypergraph is a generalization of a graph, where an edge can connect any number of vertices. A k-uniform hypergraph is a hypergraph such that all its hyperedges have size k. For more information, see Wikipedia. Let's call a particular hypergraph a hypertree if it is connected (that is, you can move from any vertex t...
apps_data_2351
The Chef has been kidnapped by aliens ( they want to utilize his excellent cooking skills :P ) and has been transported to the alien planet "ZX532". Interestingly, "ZX532" uses a different time scale which has Y AlienHours on the face of a clock (instead of the 12 hours that we have). They also have 'X*Y' AlienMinutes...
apps_data_2352
Vasya is an active Internet user. One day he came across an Internet resource he liked, so he wrote its address in the notebook. We know that the address of the written resource has format: <protocol>://<domain>.ru[/<context>] where: <protocol> can equal either "http" (without the quotes) or "ftp" (without the quote...
apps_data_2353
You are given an array a with n distinct integers. Construct an array b by permuting a such that for every non-empty subset of indices S = {x_1, x_2, ..., x_{k}} (1 ≤ x_{i} ≤ n, 0 < k < n) the sums of elements on that positions in a and b are different, i. e. $\sum_{i = 1}^{k} a_{x_{i}} \neq \sum_{i = 1}^{k} b_{x_{i}}$...
apps_data_2354
As technologies develop, manufacturers are making the process of unlocking a phone as user-friendly as possible. To unlock its new phone, Arkady's pet dog Mu-mu has to bark the password once. The phone represents a password as a string of two lowercase English letters. Mu-mu's enemy Kashtanka wants to unlock Mu-mu's p...
apps_data_2355
Given are integer sequence of length N, A = (A_1, A_2, \cdots, A_N), and an integer K. For each X such that 1 \le X \le K, find the following value: \left(\displaystyle \sum_{L=1}^{N-1} \sum_{R=L+1}^{N} (A_L+A_R)^X\right) \bmod 998244353 -----Constraints----- - All values in input are integers. - 2 \le N \le 2 \tim...
apps_data_2356
You are given two positive integers N and K. How many multisets of rational numbers satisfy all of the following conditions? - The multiset has exactly N elements and the sum of them is equal to K. - Each element of the multiset is one of 1, \frac{1}{2}, \frac{1}{4}, \frac{1}{8}, \dots. In other words, each element c...
apps_data_2357
We have a sequence A of N non-negative integers. Compute the sum of \prod _{i = 1} ^N \dbinom{B_i}{A_i} over all sequences B of N non-negative integers whose sum is at most M, and print it modulo (10^9 + 7). Here, \dbinom{B_i}{A_i}, the binomial coefficient, denotes the number of ways to choose A_i objects from B_i obj...
apps_data_2358
On the xy-plane, Snuke is going to travel from the point (x_s, y_s) to the point (x_t, y_t). He can move in arbitrary directions with speed 1. Here, we will consider him as a point without size. There are N circular barriers deployed on the plane. The center and the radius of the i-th barrier are (x_i, y_i) and r_i, re...
apps_data_2359
Given positive integers N, K and M, solve the following problem for every integer x between 1 and N (inclusive): - Find the number, modulo M, of non-empty multisets containing between 0 and K (inclusive) instances of each of the integers 1, 2, 3 \cdots, N such that the average of the elements is x. -----Constraints--...
apps_data_2360
Fox Ciel wants to write a task for a programming contest. The task is: "You are given a simple undirected graph with n vertexes. Each its edge has unit length. You should calculate the number of shortest paths between vertex 1 and vertex 2." Same with some writers, she wants to make an example with some certain output...
apps_data_2361
You are given an array $a$ of length $n$ consisting of zeros. You perform $n$ actions with this array: during the $i$-th action, the following sequence of operations appears: Choose the maximum by length subarray (continuous subsegment) consisting only of zeros, among all such segments choose the leftmost one; Let th...
apps_data_2362
$n$ robots have escaped from your laboratory! You have to find them as soon as possible, because these robots are experimental, and their behavior is not tested yet, so they may be really dangerous! Fortunately, even though your robots have escaped, you still have some control over them. First of all, you know the loc...
apps_data_2363
There are $n$ athletes in front of you. Athletes are numbered from $1$ to $n$ from left to right. You know the strength of each athlete — the athlete number $i$ has the strength $s_i$. You want to split all athletes into two teams. Each team must have at least one athlete, and each athlete must be exactly in one team....
apps_data_2364
You are given an undirected unweighted graph consisting of $n$ vertices and $m$ edges (which represents the map of Bertown) and the array of prices $p$ of length $m$. It is guaranteed that there is a path between each pair of vertices (districts). Mike has planned a trip from the vertex (district) $a$ to the vertex (d...
apps_data_2365
We guessed a permutation $p$ consisting of $n$ integers. The permutation of length $n$ is the array of length $n$ where each element from $1$ to $n$ appears exactly once. This permutation is a secret for you. For each position $r$ from $2$ to $n$ we chose some other index $l$ ($l < r$) and gave you the segment $p_l, p...
apps_data_2366
Polycarp analyzes the prices of the new berPhone. At his disposal are the prices for $n$ last days: $a_1, a_2, \dots, a_n$, where $a_i$ is the price of berPhone on the day $i$. Polycarp considers the price on the day $i$ to be bad if later (that is, a day with a greater number) berPhone was sold at a lower price. For ...
apps_data_2367
You are given two strings $s$ and $t$ both of length $n$ and both consisting of lowercase Latin letters. In one move, you can choose any length $len$ from $1$ to $n$ and perform the following operation: Choose any contiguous substring of the string $s$ of length $len$ and reverse it; at the same time choose any con...
apps_data_2368
You have $n$ gifts and you want to give all of them to children. Of course, you don't want to offend anyone, so all gifts should be equal between each other. The $i$-th gift consists of $a_i$ candies and $b_i$ oranges. During one move, you can choose some gift $1 \le i \le n$ and do one of the following operations: ...
apps_data_2369
This problem is a version of problem D from the same contest with some additional constraints and tasks. There are $n$ candies in a candy box. The type of the $i$-th candy is $a_i$ ($1 \le a_i \le n$). You have to prepare a gift using some of these candies with the following restriction: the numbers of candies of ea...
apps_data_2370
The only difference between easy and hard versions is constraints. You are given a sequence $a$ consisting of $n$ positive integers. Let's define a three blocks palindrome as the sequence, consisting of at most two distinct elements (let these elements are $a$ and $b$, $a$ can be equal $b$) and is as follows: $[\unde...
apps_data_2371
You are given an array $a$ consisting of $n$ integers. You have to find the length of the smallest (shortest) prefix of elements you need to erase from $a$ to make it a good array. Recall that the prefix of the array $a=[a_1, a_2, \dots, a_n]$ is a subarray consisting several first elements: the prefix of the array $a$...
apps_data_2372
Initially, you have the array $a$ consisting of one element $1$ ($a = [1]$). In one move, you can do one of the following things: Increase some (single) element of $a$ by $1$ (choose some $i$ from $1$ to the current length of $a$ and increase $a_i$ by one); Append the copy of some (single) element of $a$ to the en...
apps_data_2373
You are given an array $a$ consisting of $n$ integers (it is guaranteed that $n$ is even, i.e. divisible by $2$). All $a_i$ does not exceed some integer $k$. Your task is to replace the minimum number of elements (replacement is the following operation: choose some index $i$ from $1$ to $n$ and replace $a_i$ with some...
apps_data_2374
You are given a system of pipes. It consists of two rows, each row consists of $n$ pipes. The top left pipe has the coordinates $(1, 1)$ and the bottom right — $(2, n)$. There are six types of pipes: two types of straight pipes and four types of curved pipes. Here are the examples of all six types: [Image] Types of ...
apps_data_2375
The only difference between easy and hard versions is constraints. You are given a sequence $a$ consisting of $n$ positive integers. Let's define a three blocks palindrome as the sequence, consisting of at most two distinct elements (let these elements are $a$ and $b$, $a$ can be equal $b$) and is as follows: $[\unde...
apps_data_2376
You are given a tree (connected graph without cycles) consisting of $n$ vertices. The tree is unrooted — it is just a connected undirected graph without cycles. In one move, you can choose exactly $k$ leaves (leaf is such a vertex that is connected to only one another vertex) connected to the same vertex and remove th...
apps_data_2377
This is an easy version of the problem. In this version, all numbers in the given array are distinct and the constraints on $n$ are less than in the hard version of the problem. You are given an array $a$ of $n$ integers (there are no equals elements in the array). You can perform the following operations on array ele...
apps_data_2378
Recently you have bought a snow walking robot and brought it home. Suppose your home is a cell $(0, 0)$ on an infinite grid. You also have the sequence of instructions of this robot. It is written as the string $s$ consisting of characters 'L', 'R', 'U' and 'D'. If the robot is in the cell $(x, y)$ right now, he can m...
apps_data_2379
You are given a binary string $s$ consisting of $n$ zeros and ones. Your task is to divide the given string into the minimum number of subsequences in such a way that each character of the string belongs to exactly one subsequence and each subsequence looks like "010101 ..." or "101010 ..." (i.e. the subsequence shoul...
apps_data_2380
You are given a garland consisting of $n$ lamps. States of the lamps are represented by the string $s$ of length $n$. The $i$-th character of the string $s_i$ equals '0' if the $i$-th lamp is turned off or '1' if the $i$-th lamp is turned on. You are also given a positive integer $k$. In one move, you can choose one l...
apps_data_2381
There is a frog staying to the left of the string $s = s_1 s_2 \ldots s_n$ consisting of $n$ characters (to be more precise, the frog initially stays at the cell $0$). Each character of $s$ is either 'L' or 'R'. It means that if the frog is staying at the $i$-th cell and the $i$-th character is 'L', the frog can jump o...
apps_data_2382
You are given $n$ strings $a_1, a_2, \ldots, a_n$: all of them have the same length $m$. The strings consist of lowercase English letters. Find any string $s$ of length $m$ such that each of the given $n$ strings differs from $s$ in at most one position. Formally, for each given string $a_i$, there is no more than one...
apps_data_2383
Find the minimum area of a square land on which you can place two identical rectangular $a \times b$ houses. The sides of the houses should be parallel to the sides of the desired square land. Formally, You are given two identical rectangles with side lengths $a$ and $b$ ($1 \le a, b \le 100$) — positive integers (y...
apps_data_2384
This is a hard version of the problem. In this version, the given array can contain equal elements and the constraints on $n$ are greater than in the easy version of the problem. You are given an array $a$ of $n$ integers (the given array can contain equal elements). You can perform the following operations on array e...
apps_data_2385
There is a rectangular grid of size $n \times m$. Each cell of the grid is colored black ('0') or white ('1'). The color of the cell $(i, j)$ is $c_{i, j}$. You are also given a map of directions: for each cell, there is a direction $s_{i, j}$ which is one of the four characters 'U', 'R', 'D' and 'L'. If $s_{i, j}$ ...
apps_data_2386
A permutation of length $n$ is a sequence of integers from $1$ to $n$ of length $n$ containing each number exactly once. For example, $[1]$, $[4, 3, 5, 1, 2]$, $[3, 2, 1]$ are permutations, and $[1, 1]$, $[0, 1]$, $[2, 2, 1, 4]$ are not. There was a permutation $p[1 \dots n]$. It was merged with itself. In other words...
apps_data_2387
Mishka wants to buy some food in the nearby shop. Initially, he has $s$ burles on his card. Mishka can perform the following operation any number of times (possibly, zero): choose some positive integer number $1 \le x \le s$, buy food that costs exactly $x$ burles and obtain $\lfloor\frac{x}{10}\rfloor$ burles as a c...
apps_data_2388
You are given an undirected unweighted connected graph consisting of $n$ vertices and $m$ edges. It is guaranteed that there are no self-loops or multiple edges in the given graph. Your task is to choose at most $\lfloor\frac{n}{2}\rfloor$ vertices in this graph so each unchosen vertex is adjacent (in other words, con...
apps_data_2389
The only difference between easy and hard versions is the size of the input. You are given a string $s$ consisting of $n$ characters, each character is 'R', 'G' or 'B'. You are also given an integer $k$. Your task is to change the minimum number of characters in the initial string $s$ so that after the changes there ...
apps_data_2390
This problem is actually a subproblem of problem G from the same contest. There are $n$ candies in a candy box. The type of the $i$-th candy is $a_i$ ($1 \le a_i \le n$). You have to prepare a gift using some of these candies with the following restriction: the numbers of candies of each type presented in a gift shou...
apps_data_2391
You are given an array $a$ consisting of $n$ integers. In one move, you can choose some index $i$ ($1 \le i \le n - 2$) and shift the segment $[a_i, a_{i + 1}, a_{i + 2}]$ cyclically to the right (i.e. replace the segment $[a_i, a_{i + 1}, a_{i + 2}]$ with $[a_{i + 2}, a_i, a_{i + 1}]$). Your task is to sort the ini...
apps_data_2392
Polycarp is reading a book consisting of $n$ pages numbered from $1$ to $n$. Every time he finishes the page with the number divisible by $m$, he writes down the last digit of this page number. For example, if $n=15$ and $m=5$, pages divisible by $m$ are $5, 10, 15$. Their last digits are $5, 0, 5$ correspondingly, the...
apps_data_2393
Polygon is not only the best platform for developing problems but also a square matrix with side $n$, initially filled with the character 0. On the polygon, military training was held. The soldiers placed a cannon above each cell in the first row and a cannon to the left of each cell in the first column. Thus, exactly...
apps_data_2394
You are given a bracket sequence $s$ of length $n$, where $n$ is even (divisible by two). The string $s$ consists of $\frac{n}{2}$ opening brackets '(' and $\frac{n}{2}$ closing brackets ')'. In one move, you can choose exactly one bracket and move it to the beginning of the string or to the end of the string (i.e. yo...
apps_data_2395
A number is ternary if it contains only digits $0$, $1$ and $2$. For example, the following numbers are ternary: $1022$, $11$, $21$, $2002$. You are given a long ternary number $x$. The first (leftmost) digit of $x$ is guaranteed to be $2$, the other digits of $x$ can be $0$, $1$ or $2$. Let's define the ternary XOR ...
apps_data_2396
You are given a string $s[1 \dots n]$ consisting of lowercase Latin letters. It is guaranteed that $n = 2^k$ for some integer $k \ge 0$. The string $s[1 \dots n]$ is called $c$-good if at least one of the following three conditions is satisfied: The length of $s$ is $1$, and it consists of the character $c$ (i.e. $s_...
apps_data_2397
Consider all binary strings of length $m$ ($1 \le m \le 60$). A binary string is a string that consists of the characters 0 and 1 only. For example, 0110 is a binary string, and 012aba is not. Obviously, there are exactly $2^m$ such strings in total. The string $s$ is lexicographically smaller than the string $t$ (bot...
apps_data_2398
You are given a table $a$ of size $2 \times n$ (i.e. two rows and $n$ columns) consisting of integers from $1$ to $n$. In one move, you can choose some column $j$ ($1 \le j \le n$) and swap values $a_{1, j}$ and $a_{2, j}$ in it. Each column can be chosen no more than once. Your task is to find the minimum number of ...
apps_data_2399
You are given a graph consisting of $n$ vertices and $m$ edges. It is not guaranteed that the given graph is connected. Some edges are already directed and you can't change their direction. Other edges are undirected and you have to choose some direction for all these edges. You have to direct undirected edges in such...