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Solve the programming task below in a Python markdown code block. You are given an array consisting of $n$ integers $a_1, a_2, \dots , a_n$ and an integer $x$. It is guaranteed that for every $i$, $1 \le a_i \le x$. Let's denote a function $f(l, r)$ which erases all values such that $l \le a_i \le r$ from the array $...
Solve the programming task below in a Python markdown code block. Ann has recently started commuting by subway. We know that a one ride subway ticket costs a rubles. Besides, Ann found out that she can buy a special ticket for m rides (she can buy it several times). It costs b rubles. Ann did the math; she will need t...
Solve the programming task below in a Python markdown code block. Alice and Bob love playing one-dimensional battle ships. They play on the field in the form of a line consisting of n square cells (that is, on a 1 × n table). At the beginning of the game Alice puts k ships on the field without telling their positions...
Solve the programming task below in a Python markdown code block. Given simple (without self-intersections) n-gon. It is not necessary convex. Also you are given m lines. For each line find the length of common part of the line and the n-gon. The boundary of n-gon belongs to polygon. It is possible that n-gon contain...
Solve the programming task below in a Python markdown code block. Alice has a string $s$. She really likes the letter "a". She calls a string good if strictly more than half of the characters in that string are "a"s. For example "aaabb", "axaa" are good strings, and "baca", "awwwa", "" (empty string) are not. Alice c...
Solve the programming task below in a Python markdown code block. Xenia lives in a city that has n houses built along the main ringroad. The ringroad houses are numbered 1 through n in the clockwise order. The ringroad traffic is one way and also is clockwise. Xenia has recently moved into the ringroad house number 1...
Solve the programming task below in a Python markdown code block. Santa Claus likes palindromes very much. There was his birthday recently. k of his friends came to him to congratulate him, and each of them presented to him a string s_{i} having the same length n. We denote the beauty of the i-th string by a_{i}. It c...
Solve the programming task below in a Python markdown code block. Tomash keeps wandering off and getting lost while he is walking along the streets of Berland. It's no surprise! In his home town, for any pair of intersections there is exactly one way to walk from one intersection to the other one. The capital of Berla...
Solve the programming task below in a Python markdown code block. Student Valera is an undergraduate student at the University. His end of term exams are approaching and he is to pass exactly n exams. Valera is a smart guy, so he will be able to pass any exam he takes on his first try. Besides, he can take several exa...
Solve the programming task below in a Python markdown code block. Mike is trying rock climbing but he is awful at it. There are n holds on the wall, i-th hold is at height a_{i} off the ground. Besides, let the sequence a_{i} increase, that is, a_{i} < a_{i} + 1 for all i from 1 to n - 1; we will call such sequence ...
Solve the programming task below in a Python markdown code block. Завтра у хоккейной команды, которой руководит Евгений, важный матч. Евгению нужно выбрать шесть игроков, которые выйдут на лед в стартовом составе: один вратарь, два защитника и три нападающих. Так как это стартовый состав, Евгения больше волнует, наск...
Solve the programming task below in a Python markdown code block. Arkady invited Anna for a dinner to a sushi restaurant. The restaurant is a bit unusual: it offers $n$ pieces of sushi aligned in a row, and a customer has to choose a continuous subsegment of these sushi to buy. The pieces of sushi are of two types: e...
Solve the programming task below in a Python markdown code block. Ostap already settled down in Rio de Janiero suburb and started to grow a tree in his garden. Recall that a tree is a connected undirected acyclic graph. Ostap's tree now has n vertices. He wants to paint some vertices of the tree black such that from...
Solve the programming task below in a Python markdown code block. Sereja and his friends went to a picnic. The guys had n soda bottles just for it. Sereja forgot the bottle opener as usual, so the guys had to come up with another way to open bottles. Sereja knows that the i-th bottle is from brand a_{i}, besides, you...
Solve the programming task below in a Python markdown code block. You are given N items. The value of the i-th item (1 \leq i \leq N) is v_i. Your have to select at least A and at most B of these items. Under this condition, find the maximum possible arithmetic mean of the values of selected items. Additionally, f...
Solve the programming task below in a Python markdown code block. Given are N points (x_i, y_i) in a two-dimensional plane. Find the minimum radius of a circle such that all the points are inside or on it. -----Constraints----- - 2 \leq N \leq 50 - 0 \leq x_i \leq 1000 - 0 \leq y_i \leq 1000 - The given N points ...
Solve the programming task below in a Python markdown code block. Given is an integer S. Find how many sequences there are whose terms are all integers greater than or equal to 3, and whose sum is equal to S. The answer can be very large, so output it modulo 10^9 + 7. -----Constraints----- - 1 \leq S \leq 2000 - Al...
Solve the programming task below in a Python markdown code block. Ibis is fighting with a monster. The health of the monster is H. Ibis can cast N kinds of spells. Casting the i-th spell decreases the monster's health by A_i, at the cost of B_i Magic Points. The same spell can be cast multiple times. There is no way o...
Solve the programming task below in a Python markdown code block. We have N+1 integers: 10^{100}, 10^{100}+1, ..., 10^{100}+N. We will choose K or more of these integers. Find the number of possible values of the sum of the chosen numbers, modulo (10^9+7). -----Constraints----- - 1 \leq N \leq 2\times 10^5 - 1 \leq...
Solve the programming task below in a Python markdown code block. You've got array a[1], a[2], ..., a[n], consisting of n integers. Count the number of ways to split all the elements of the array into three contiguous parts so that the sum of elements in each part is the same. More formally, you need to find the num...
Solve the programming task below in a Python markdown code block. Sasha and Dima want to buy two $n$-tier cakes. Each cake should consist of $n$ different tiers: from the size of $1$ to the size of $n$. Tiers should go in order from the smallest to the biggest (from top to bottom). They live on the same street, there...
Solve the programming task below in a Python markdown code block. There are $n$ pillars aligned in a row and numbered from $1$ to $n$. Initially each pillar contains exactly one disk. The $i$-th pillar contains a disk having radius $a_i$. You can move these disks from one pillar to another. You can take a disk from ...
Solve the programming task below in a Python markdown code block. Bill is a famous mathematician in BubbleLand. Thanks to his revolutionary math discoveries he was able to make enough money to build a beautiful house. Unfortunately, for not paying property tax on time, court decided to punish Bill by making him lose a...
Solve the programming task below in a Python markdown code block. Recently Monocarp got a job. His working day lasts exactly $m$ minutes. During work, Monocarp wants to drink coffee at certain moments: there are $n$ minutes $a_1, a_2, \dots, a_n$, when he is able and willing to take a coffee break (for the sake of sim...
Solve the programming task below in a Python markdown code block. The Queen of England has n trees growing in a row in her garden. At that, the i-th (1 ≤ i ≤ n) tree from the left has height a_{i} meters. Today the Queen decided to update the scenery of her garden. She wants the trees' heights to meet the condition: f...
Solve the programming task below in a Python markdown code block. To make a paper airplane, one has to use a rectangular piece of paper. From a sheet of standard size you can make $s$ airplanes. A group of $k$ people decided to make $n$ airplanes each. They are going to buy several packs of paper, each of them contai...
Solve the programming task below in a Python markdown code block. After Vitaly was expelled from the university, he became interested in the graph theory. Vitaly especially liked the cycles of an odd length in which each vertex occurs at most once. Vitaly was wondering how to solve the following problem. You are giv...
Solve the programming task below in a Python markdown code block. You are given a positive integer $m$ and two integer sequence: $a=[a_1, a_2, \ldots, a_n]$ and $b=[b_1, b_2, \ldots, b_n]$. Both of these sequence have a length $n$. Permutation is a sequence of $n$ different positive integers from $1$ to $n$. For exam...
Solve the programming task below in a Python markdown code block. Hideo Kojima has just quit his job at Konami. Now he is going to find a new place to work. Despite being such a well-known person, he still needs a CV to apply for a job. During all his career Hideo has produced n games. Some of them were successful, s...
Solve the programming task below in a Python markdown code block. The problem describes the properties of a command line. The description somehow resembles the one you usually see in real operating systems. However, there are differences in the behavior. Please make sure you've read the statement attentively and use i...
Solve the programming task below in a Python markdown code block. Bob is decorating his kitchen, more precisely, the floor. He has found a prime candidate for the tiles he will use. They come in a simple form factor — a square tile that is diagonally split into white and black part as depicted in the figure below. [Im...
Solve the programming task below in a Python markdown code block. New Year is coming in Line World! In this world, there are n cells numbered by integers from 1 to n, as a 1 × n board. People live in cells. However, it was hard to move between distinct cells, because of the difficulty of escaping the cell. People want...
Solve the programming task below in a Python markdown code block. Ashish has a tree consisting of $n$ nodes numbered $1$ to $n$ rooted at node $1$. The $i$-th node in the tree has a cost $a_i$, and binary digit $b_i$ is written in it. He wants to have binary digit $c_i$ written in the $i$-th node in the end. To achie...
Solve the programming task below in a Python markdown code block. The first algorithm for detecting a face on the image working in realtime was developed by Paul Viola and Michael Jones in 2001. A part of the algorithm is a procedure that computes Haar features. As part of this task, we consider a simplified model of ...
Solve the programming task below in a Python markdown code block. The end of the school year is near and Ms. Manana, the teacher, will soon have to say goodbye to a yet another class. She decided to prepare a goodbye present for her n students and give each of them a jigsaw puzzle (which, as wikipedia states, is a til...
Solve the programming task below in a Python markdown code block. A group of n schoolboys decided to ride bikes. As nobody of them has a bike, the boys need to rent them. The renting site offered them m bikes. The renting price is different for different bikes, renting the j-th bike costs p_{j} rubles. In total, the...
Solve the programming task below in a Python markdown code block. Let's call a number k-good if it contains all digits not exceeding k (0, ..., k). You've got a number k and an array a containing n numbers. Find out how many k-good numbers are in a (count each number every time it occurs in array a). -----Input-----...
Solve the programming task below in a Python markdown code block. Little Tanya decided to present her dad a postcard on his Birthday. She has already created a message — string s of length n, consisting of uppercase and lowercase English letters. Tanya can't write yet, so she found a newspaper and decided to cut out t...
Solve the programming task below in a Python markdown code block. Iahub is training for the IOI. What is a better way to train than playing a Zuma-like game? There are n balls put in a row. Each ball is colored in one of k colors. Initially the row doesn't contain three or more contiguous balls with the same color. ...
Solve the programming task below in a Python markdown code block. A country has n cities. Initially, there is no road in the country. One day, the king decides to construct some roads connecting pairs of cities. Roads can be traversed either way. He wants those roads to be constructed in such a way that it is possible...
Solve the programming task below in a Python markdown code block. One day Vasya was on a physics practical, performing the task on measuring the capacitance. He followed the teacher's advice and did as much as n measurements, and recorded the results in the notebook. After that he was about to show the results to the ...
Solve the programming task below in a Python markdown code block. Today Adilbek is taking his probability theory test. Unfortunately, when Adilbek arrived at the university, there had already been a long queue of students wanting to take the same test. Adilbek has estimated that he will be able to start the test only ...
Solve the programming task below in a Python markdown code block. Alyona decided to go on a diet and went to the forest to get some apples. There she unexpectedly found a magic rooted tree with root in the vertex 1, every vertex and every edge of which has a number written on. The girl noticed that some of the tree's...
Solve the programming task below in a Python markdown code block. Yaroslav thinks that two strings s and w, consisting of digits and having length n are non-comparable if there are two numbers, i and j (1 ≤ i, j ≤ n), such that s_{i} > w_{i} and s_{j} < w_{j}. Here sign s_{i} represents the i-th digit of string s, sim...
Solve the programming task below in a Python markdown code block. You have a Petri dish with bacteria and you are preparing to dive into the harsh micro-world. But, unfortunately, you don't have any microscope nearby, so you can't watch them. You know that you have $n$ bacteria in the Petri dish and size of the $i$-t...
Solve the programming task below in a Python markdown code block. Ivan unexpectedly saw a present from one of his previous birthdays. It is array of $n$ numbers from $1$ to $200$. Array is old and some numbers are hard to read. Ivan remembers that for all elements at least one of its neighbours ls not less than it, mo...
Solve the programming task below in a Python markdown code block. Recently Pashmak has been employed in a transportation company. The company has k buses and has a contract with a school which has n students. The school planned to take the students to d different places for d days (each day in one place). Each day the...
Solve the programming task below in a Python markdown code block. You've got an n × m matrix. The matrix consists of integers. In one move, you can apply a single transformation to the matrix: choose an arbitrary element of the matrix and increase it by 1. Each element can be increased an arbitrary number of times. Y...
Solve the programming task below in a Python markdown code block. Shaass has n books. He wants to make a bookshelf for all his books. He wants the bookshelf's dimensions to be as small as possible. The thickness of the i-th book is t_{i} and its pages' width is equal to w_{i}. The thickness of each book is either 1 or...
Solve the programming task below in a Python markdown code block. The Saratov State University Olympiad Programmers Training Center (SSU OPTC) has n students. For each student you know the number of times he/she has participated in the ACM ICPC world programming championship. According to the ACM ICPC rules, each pers...
Solve the programming task below in a Python markdown code block. You are given a tree consisting of $n$ vertices. A tree is an undirected connected acyclic graph. [Image] Example of a tree. You have to paint each vertex into one of three colors. For each vertex, you know the cost of painting it in every color. You...
Solve the programming task below in a Python markdown code block. All our characters have hobbies. The same is true for Fedor. He enjoys shopping in the neighboring supermarket. The goods in the supermarket have unique integer ids. Also, for every integer there is a product with id equal to this integer. Fedor has n...
Solve the programming task below in a Python markdown code block. You are given a string $s=s_1s_2\dots s_n$ of length $n$, which only contains digits $1$, $2$, ..., $9$. A substring $s[l \dots r]$ of $s$ is a string $s_l s_{l + 1} s_{l + 2} \ldots s_r$. A substring $s[l \dots r]$ of $s$ is called even if the number ...
Solve the programming task below in a Python markdown code block. Inna and Dima bought a table of size n × m in the shop. Each cell of the table contains a single letter: "D", "I", "M", "A". Inna loves Dima, so she wants to go through his name as many times as possible as she moves through the table. For that, Inna a...
Solve the programming task below in a Python markdown code block. The Cybernetics Failures (CF) organisation made a prototype of a bomb technician robot. To find the possible problems it was decided to carry out a series of tests. At the beginning of each test the robot prototype will be placed in cell (x_0, y_0) of a...
Solve the programming task below in a Python markdown code block. Pasha decided to invite his friends to a tea party. For that occasion, he has a large teapot with the capacity of w milliliters and 2n tea cups, each cup is for one of Pasha's friends. The i-th cup can hold at most a_{i} milliliters of water. It turned...
Solve the programming task below in a Python markdown code block. Let $n$ be an integer. Consider all permutations on integers $1$ to $n$ in lexicographic order, and concatenate them into one big sequence $P$. For example, if $n = 3$, then $P = [1, 2, 3, 1, 3, 2, 2, 1, 3, 2, 3, 1, 3, 1, 2, 3, 2, 1]$. The length of thi...
Solve the programming task below in a Python markdown code block. You're given an integer $n$. For every integer $i$ from $2$ to $n$, assign a positive integer $a_i$ such that the following conditions hold: For any pair of integers $(i,j)$, if $i$ and $j$ are coprime, $a_i \neq a_j$. The maximal value of all $a_i$ s...
Solve the programming task below in a Python markdown code block. The main city magazine offers its readers an opportunity to publish their ads. The format of the ad should be like this: There are space-separated non-empty words of lowercase and uppercase Latin letters. There are hyphen characters '-' in some words,...
Solve the programming task below in a Python markdown code block. Vanya walks late at night along a straight street of length l, lit by n lanterns. Consider the coordinate system with the beginning of the street corresponding to the point 0, and its end corresponding to the point l. Then the i-th lantern is at the poi...
Solve the programming task below in a Python markdown code block. Generous sponsors of the olympiad in which Chloe and Vladik took part allowed all the participants to choose a prize for them on their own. Christmas is coming, so sponsors decided to decorate the Christmas tree with their prizes. They took n prizes f...
Solve the programming task below in a Python markdown code block. Xenia has a set of weights and pan scales. Each weight has an integer weight from 1 to 10 kilos. Xenia is going to play with scales and weights a little. For this, she puts weights on the scalepans, one by one. The first weight goes on the left scalepan...
Solve the programming task below in a Python markdown code block. Dasha logged into the system and began to solve problems. One of them is as follows: Given two sequences a and b of length n each you need to write a sequence c of length n, the i-th element of which is calculated as follows: c_{i} = b_{i} - a_{i}. Ab...
Solve the programming task below in a Python markdown code block. After you had helped George and Alex to move in the dorm, they went to help their friend Fedor play a new computer game «Call of Soldiers 3». The game has (m + 1) players and n types of soldiers in total. Players «Call of Soldiers 3» are numbered form ...
Solve the programming task below in a Python markdown code block. You are given $n$ numbers $a_1, a_2, \ldots, a_n$. Is it possible to arrange them in a circle in such a way that every number is strictly less than the sum of its neighbors? For example, for the array $[1, 4, 5, 6, 7, 8]$, the arrangement on the left i...
Solve the programming task below in a Python markdown code block. Ken loves ken-ken-pa (Japanese version of hopscotch). Today, he will play it on a directed graph G. G consists of N vertices numbered 1 to N, and M edges. The i-th edge points from Vertex u_i to Vertex v_i. First, Ken stands on Vertex S. He wants to rea...
Solve the programming task below in a Python markdown code block. Given are N positive integers A_1,...,A_N. Consider positive integers B_1, ..., B_N that satisfy the following condition. Condition: For any i, j such that 1 \leq i < j \leq N, A_i B_i = A_j B_j holds. Find the minimum possible value of B_1 + ... + B_N ...
Solve the programming task below in a Python markdown code block. There is a grid with N rows and N columns of squares. Let (i,j) be the square at the i-th row from the top and the j-th column from the left. These squares have to be painted in one of the C colors from Color 1 to Color C. Initially, (i,j) is painted in...
Solve the programming task below in a Python markdown code block. There are N mountains in a circle, called Mountain 1, Mountain 2, ..., Mountain N in clockwise order. N is an odd number. Between these mountains, there are N dams, called Dam 1, Dam 2, ..., Dam N. Dam i (1 \leq i \leq N) is located between Mountain i a...
Solve the programming task below in a Python markdown code block. Theater stage is a rectangular field of size n × m. The director gave you the stage's plan which actors will follow. For each cell it is stated in the plan if there would be an actor in this cell or not. You are to place a spotlight on the stage in som...
Solve the programming task below in a Python markdown code block. Let's define a forest as a non-directed acyclic graph (also without loops and parallel edges). One day Misha played with the forest consisting of n vertices. For each vertex v from 0 to n - 1 he wrote down two integers, degree_{v} and s_{v}, were the fi...
Solve the programming task below in a Python markdown code block. Inna loves digit 9 very much. That's why she asked Dima to write a small number consisting of nines. But Dima must have misunderstood her and he wrote a very large number a, consisting of digits from 1 to 9. Inna wants to slightly alter the number Dima...
Solve the programming task below in a Python markdown code block. The police department of your city has just started its journey. Initially, they don’t have any manpower. So, they started hiring new recruits in groups. Meanwhile, crimes keeps occurring within the city. One member of the police force can investigate ...
Solve the programming task below in a Python markdown code block. While walking down the street Vanya saw a label "Hide&Seek". Because he is a programmer, he used & as a bitwise AND for these two words represented as a integers in base 64 and got new word. Now Vanya thinks of some string s and wants to know the number...
Solve the programming task below in a Python markdown code block. Pavel has several sticks with lengths equal to powers of two. He has $a_0$ sticks of length $2^0 = 1$, $a_1$ sticks of length $2^1 = 2$, ..., $a_{n-1}$ sticks of length $2^{n-1}$. Pavel wants to make the maximum possible number of triangles using the...
Solve the programming task below in a Python markdown code block. Smart Beaver decided to be not only smart, but also a healthy beaver! And so he began to attend physical education classes at school X. In this school, physical education has a very creative teacher. One of his favorite warm-up exercises is throwing bal...
Solve the programming task below in a Python markdown code block. In this task you need to process a set of stock exchange orders and use them to create order book. An order is an instruction of some participant to buy or sell stocks on stock exchange. The order number i has price p_{i}, direction d_{i} — buy or sell...
Solve the programming task below in a Python markdown code block. Bob is a duck. He wants to get to Alice's nest, so that those two can duck! [Image] Duck is the ultimate animal! (Image courtesy of See Bang) The journey can be represented as a straight line, consisting of $n$ segments. Bob is located to the left of ...
Solve the programming task below in a Python markdown code block. Berland is going through tough times — the dirt price has dropped and that is a blow to the country's economy. Everybody knows that Berland is the top world dirt exporter! The President of Berland was forced to leave only k of the currently existing n ...
Solve the programming task below in a Python markdown code block. Dima took up the biology of bacteria, as a result of his experiments, he invented k types of bacteria. Overall, there are n bacteria at his laboratory right now, and the number of bacteria of type i equals c_{i}. For convenience, we will assume that all...
Solve the programming task below in a Python markdown code block. Alex enjoys performing magic tricks. He has a trick that requires a deck of n cards. He has m identical decks of n different cards each, which have been mixed together. When Alex wishes to perform the trick, he grabs n cards at random and performs the t...
Solve the programming task below in a Python markdown code block. Vasya owns a cornfield which can be defined with two integers $n$ and $d$. The cornfield can be represented as rectangle with vertices having Cartesian coordinates $(0, d), (d, 0), (n, n - d)$ and $(n - d, n)$. [Image] An example of a cornfield with $...
Solve the programming task below in a Python markdown code block. You are given a non-decreasing array of non-negative integers $a_1, a_2, \ldots, a_n$. Also you are given a positive integer $k$. You want to find $m$ non-decreasing arrays of non-negative integers $b_1, b_2, \ldots, b_m$, such that: The size of $b_i$...
Solve the programming task below in a Python markdown code block. Suppose there is a $h \times w$ grid consisting of empty or full cells. Let's make some definitions: $r_{i}$ is the number of consecutive full cells connected to the left side in the $i$-th row ($1 \le i \le h$). In particular, $r_i=0$ if the leftmos...
Solve the programming task below in a Python markdown code block. Tsumugi brought $n$ delicious sweets to the Light Music Club. They are numbered from $1$ to $n$, where the $i$-th sweet has a sugar concentration described by an integer $a_i$. Yui loves sweets, but she can eat at most $m$ sweets each day for health re...
Solve the programming task below in a Python markdown code block. In this problem, a $n \times m$ rectangular matrix $a$ is called increasing if, for each row of $i$, when go from left to right, the values strictly increase (that is, $a_{i,1}<a_{i,2}<\dots<a_{i,m}$) and for each column $j$, when go from top to bottom,...
Solve the programming task below in a Python markdown code block. Nauuo is a girl who loves playing chess. One day she invented a game by herself which needs $n$ chess pieces to play on a $m\times m$ chessboard. The rows and columns are numbered from $1$ to $m$. We denote a cell on the intersection of the $r$-th row ...
Solve the programming task below in a Python markdown code block. Igor has been into chess for a long time and now he is sick of the game by the ordinary rules. He is going to think of new rules of the game and become world famous. Igor's chessboard is a square of size n × n cells. Igor decided that simple rules guar...
Solve the programming task below in a Python markdown code block. A long time ago, in a galaxy far far away two giant IT-corporations Pineapple and Gogol continue their fierce competition. Crucial moment is just around the corner: Gogol is ready to release it's new tablet Lastus 3000. This new device is equipped with...
Solve the programming task below in a Python markdown code block. The circle line of the Berland subway has n stations. We know the distances between all pairs of neighboring stations: d_1 is the distance between the 1-st and the 2-nd station; d_2 is the distance between the 2-nd and the 3-rd station; ... d_{...
Solve the programming task below in a Python markdown code block. Leo Jr. draws pictures in his notebook with checkered sheets (that is, each sheet has a regular square grid printed on it). We can assume that the sheets are infinitely large in any direction. To draw a picture, Leo Jr. colors some of the cells on a sh...
Solve the programming task below in a Python markdown code block. You are given a functional graph. It is a directed graph, in which from each vertex goes exactly one arc. The vertices are numerated from 0 to n - 1. Graph is given as the array f_0, f_1, ..., f_{n} - 1, where f_{i} — the number of vertex to which goes...
Solve the programming task below in a Python markdown code block. Okabe needs to renovate the Future Gadget Laboratory after he tried doing some crazy experiments! The lab is represented as an n by n square grid of integers. A good lab is defined as a lab in which every number not equal to 1 can be expressed as the su...
Solve the programming task below in a Python markdown code block. There are $n$ children, who study at the school №41. It is well-known that they are good mathematicians. Once at a break, they arranged a challenge for themselves. All children arranged in a row and turned heads either to the left or to the right. Chil...
Solve the programming task below in a Python markdown code block. You are given an undirected connected weighted graph consisting of $n$ vertices and $m$ edges. Let's denote the length of the shortest path from vertex $1$ to vertex $i$ as $d_i$. You have to erase some edges of the graph so that at most $k$ edges rem...
Solve the programming task below in a Python markdown code block. You are given an array $a_1, a_2, \dots, a_n$ of integer numbers. Your task is to divide the array into the maximum number of segments in such a way that: each element is contained in exactly one segment; each segment contains at least one element;...
Solve the programming task below in a Python markdown code block. Vasya is an administrator of a public page of organization "Mouse and keyboard" and his everyday duty is to publish news from the world of competitive programming. For each news he also creates a list of hashtags to make searching for a particular topic...
Solve the programming task below in a Python markdown code block. You are given an integer L. Construct a directed graph that satisfies the conditions below. The graph may contain multiple edges between the same pair of vertices. It can be proved that such a graph always exists. - The number of vertices, N, is at mos...
Solve the programming task below in a Python markdown code block. Snuke has decided to play with a six-sided die. Each of its six sides shows an integer 1 through 6, and two numbers on opposite sides always add up to 7. Snuke will first put the die on the table with an arbitrary side facing upward, then repeatedly per...
Solve the programming task below in a Python markdown code block. We have a tree with N vertices numbered 1 to N. The i-th edge in the tree connects Vertex u_i and Vertex v_i, and its length is w_i. Your objective is to paint each vertex in the tree white or black (it is fine to paint all vertices the same color) so t...