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Solve the programming task below in a Python markdown code block. In a laboratory, an assistant, Nathan Wada, is measuring weight differences between sample pieces pair by pair. He is using a balance because it can more precisely measure the weight difference between two samples than a spring scale when the samples ha...
Solve the programming task below in a Python markdown code block. Matryoshka Matryoshka is a famous Russian folk craft doll. Matryoshka can be divided into upper and lower parts, and when opened, there is another smaller doll inside. The nesting structure is such that when the small doll that appears is opened, a sma...
Solve the programming task below in a Python markdown code block. Cutlet Sandwich In some worlds, there are $ X $ types of "sandwiches", $ Y $ types of "cutlets", and $ Z $ types of "curry" foods. There is a $ N $ type of "cutlet sandwich" in this world, and the $ i $ type of cutlet sandwich is made from the $ A_i $...
Solve the programming task below in a Python markdown code block. Constraints * 1 ≤ |V| ≤ 1000 * 0 ≤ |E| ≤ 2000 * -10000 ≤ di ≤ 10000 * There are no parallel edges * There are no self-loops Input An edge-weighted graph G (V, E) and the source r. |V| |E| r s0 t0 d0 s1 t1 d1 : s|E|-1 t|E|-1 d|E|-1 |V| is the numb...
Solve the programming task below in a Python markdown code block. Initially there was an array a consisting of n integers. Positions in it are numbered from 1 to n. Exactly q queries were performed on the array. During the i-th query some segment (l_i, r_i) (1 ≤ l_i ≤ r_i ≤ n) was selected and values of elements on p...
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 pillar i a...
Solve the programming task below in a Python markdown code block. Petya's friends made him a birthday present — a bracket sequence. Petya was quite disappointed with his gift, because he dreamed of correct bracket sequence, yet he told his friends nothing about his dreams and decided to fix present himself. To make ...
Solve the programming task below in a Python markdown code block. Recall that a binary search tree is a rooted binary tree, whose nodes each store a key and each have at most two distinguished subtrees, left and right. The key in each node must be greater than any key stored in the left subtree, and less than any key ...
Solve the programming task below in a Python markdown code block. Santa Claus has received letters from n different kids throughout this year. Of course, each kid wants to get some presents from Santa: in particular, the i-th kid asked Santa to give them one of k_i different items as a present. Some items could have b...
Solve the programming task below in a Python markdown code block. Anna and Maria are in charge of the math club for junior students. When the club gathers together, the students behave badly. They've brought lots of shoe laces to the club and got tied with each other. Specifically, each string ties together two studen...
Solve the programming task below in a Python markdown code block. Denis, after buying flowers and sweets (you will learn about this story in the next task), went to a date with Nastya to ask her to become a couple. Now, they are sitting in the cafe and finally... Denis asks her to be together, but ... Nastya doesn't g...
Solve the programming task below in a Python markdown code block. A permutation of length n is an array consisting of n distinct integers from 1 to n in arbitrary order. For example, [2,3,1,5,4] is a permutation, but [1,2,2] is not a permutation (2 appears twice in the array) and [1,3,4] is also not a permutation (n=3...
Solve the programming task below in a Python markdown code block. 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); * Ap...
Solve the programming task below in a Python markdown code block. The Super Duper Secret Meeting of the Super Duper Secret Military Squad takes place in a Super Duper Secret Place. The place is an infinite plane with introduced Cartesian coordinate system. The meeting table is represented as a rectangle whose sides ar...
Solve the programming task below in a Python markdown code block. Let's define a multiplication operation between a string a and a positive integer x: a ⋅ x is the string that is a result of writing x copies of a one after another. For example, "abc" ⋅~2~= "abcabc", "a" ⋅~5~= "aaaaa". A string a is divisible by anoth...
Solve the programming task below in a Python markdown code block. You are given a string s of length n consisting only of the characters 0 and 1. You perform the following operation until the string becomes empty: choose some consecutive substring of equal characters, erase it from the string and glue the remaining t...
Solve the programming task below in a Python markdown code block. You are given two polynomials: * P(x) = a0·xn + a1·xn - 1 + ... + an - 1·x + an and * Q(x) = b0·xm + b1·xm - 1 + ... + bm - 1·x + bm. Calculate limit <image>. Input The first line contains two space-separated integers n and m (0 ≤ n, m ≤ 100...
Solve the programming task below in a Python markdown code block. A bracket sequence is called regular if it is possible to obtain correct arithmetic expression by inserting characters «+» and «1» into this sequence. For example, sequences «(())()», «()» and «(()(()))» are regular, while «)(», «(()» and «(()))(» are n...
Solve the programming task below in a Python markdown code block. Iahub has drawn a set of n points in the cartesian plane which he calls "special points". A quadrilateral is a simple polygon without self-intersections with four sides (also called edges) and four vertices (also called corners). Please note that a quad...
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 pj rubles. In total, the bo...
Solve the programming task below in a Python markdown code block. George is a cat, so he really likes to play. Most of all he likes to play with his array of positive integers b. During the game, George modifies the array by using special changes. Let's mark George's current array as b1, b2, ..., b|b| (record |b| deno...
Solve the programming task below in a Python markdown code block. Pasha has a positive integer a without leading zeroes. Today he decided that the number is too small and he should make it larger. Unfortunately, the only operation Pasha can do is to swap two adjacent decimal digits of the integer. Help Pasha count th...
Solve the programming task below in a Python markdown code block. One day Vasya came across three Berland coins. They didn't have any numbers that's why Vasya didn't understand how their denominations differ. He supposed that if one coin is heavier than the other one, then it should be worth more. Vasya weighed all th...
Solve the programming task below in a Python markdown code block. Let's define the sum of two permutations p and q of numbers 0, 1, ..., (n - 1) as permutation <image>, where Perm(x) is the x-th lexicographically permutation of numbers 0, 1, ..., (n - 1) (counting from zero), and Ord(p) is the number of permutation p ...
Solve the programming task below in a Python markdown code block. There are many anime that are about "love triangles": Alice loves Bob, and Charlie loves Bob as well, but Alice hates Charlie. You are thinking about an anime which has n characters. The characters are labeled from 1 to n. Every pair of two characters c...
Solve the programming task below in a Python markdown code block. In Absurdistan, there are n towns (numbered 1 through n) and m bidirectional railways. There is also an absurdly simple road network — for each pair of different towns x and y, there is a bidirectional road between towns x and y if and only if there is ...
Solve the programming task below in a Python markdown code block. A MIPT student named Misha has a birthday today, and he decided to celebrate it in his country house in suburban Moscow. n friends came by, and after a typical party they decided to play blind man's buff. The birthday boy gets blindfolded and the other...
Solve the programming task below in a Python markdown code block. In an attempt to escape the Mischievous Mess Makers' antics, Farmer John has abandoned his farm and is traveling to the other side of Bovinia. During the journey, he and his k cows have decided to stay at the luxurious Grand Moo-dapest Hotel. The hotel ...
Solve the programming task below in a Python markdown code block. Every year, hundreds of people come to summer camps, they learn new algorithms and solve hard problems. This is your first year at summer camp, and you are asked to solve the following problem. All integers starting with 1 are written in one line. The ...
Solve the programming task below in a Python markdown code block. Efim just received his grade for the last test. He studies in a special school and his grade can be equal to any positive decimal fraction. First he got disappointed, as he expected a way more pleasant result. Then, he developed a tricky plan. Each seco...
Solve the programming task below in a Python markdown code block. Vasya plays The Elder Trolls IV: Oblivon. Oh, those creators of computer games! What they do not come up with! Absolutely unique monsters have been added to the The Elder Trolls IV: Oblivon. One of these monsters is Unkillable Slug. Why it is "Unkillabl...
Solve the programming task below in a Python markdown code block. Rick and Morty are playing their own version of Berzerk (which has nothing in common with the famous Berzerk game). This game needs a huge space, so they play it with a computer. In this game there are n objects numbered from 1 to n arranged in a circl...
Solve the programming task below in a Python markdown code block. It's one more school day now. Sasha doesn't like classes and is always bored at them. So, each day he invents some game and plays in it alone or with friends. Today he invented one simple game to play with Lena, with whom he shares a desk. The rules ar...
Solve the programming task below in a Python markdown code block. Slava plays his favorite game "Peace Lightning". Now he is flying a bomber on a very specific map. Formally, map is a checkered field of size 1 × n, the cells of which are numbered from 1 to n, in each cell there can be one or several tanks. Slava does...
Solve the programming task below in a Python markdown code block. Count the number of distinct sequences a1, a2, ..., an (1 ≤ ai) consisting of positive integers such that gcd(a1, a2, ..., an) = x and <image>. As this number could be large, print the answer modulo 109 + 7. gcd here means the [greatest common divisor]...
Solve the programming task below in a Python markdown code block. Dima is a beginner programmer. During his working process, he regularly has to repeat the following operation again and again: to remove every second element from the array. One day he has been bored with easy solutions of this problem, and he has come ...
Solve the programming task below in a Python markdown code block. Petya studies at university. The current academic year finishes with n special days. Petya needs to pass m exams in those special days. The special days in this problem are numbered from 1 to n. There are three values about each exam: * s_i — the da...
Solve the programming task below in a Python markdown code block. Mishka started participating in a programming contest. There are n problems in the contest. Mishka's problem-solving skill is equal to k. Mishka arranges all problems from the contest into a list. Because of his weird principles, Mishka only solves pro...
Solve the programming task below in a Python markdown code block. Naruto is a fan of numbers, he likes to play with them. This time he decided to multiply numbers and produce output. After every k elements he decides to find x^m, where x is the multiplication till k elements and m is a random number that naruto takes....
Solve the programming task below in a Python markdown code block. After Joeffrey chocked to death, Cercei blamed Tyrian for his death. After seeing his love, Shae betrayed him, he demanded trial by combat. Now this combat is not with swords but with logic and problem solving. Tywin will ask Tyrian questions and he hav...
Solve the programming task below in a Python markdown code block. Shil is your new boss and he likes palindromes very much. Palindrome is a string that can be read the same way in either direction, from the left to the right and from the right to the left. (ex. madam , aabaa, racecar) Given a string S , beautiful ...
Solve the programming task below in a Python markdown code block. In this problem, we use the 24-hour clock. Takahashi gets up exactly at the time H_1 : M_1 and goes to bed exactly at the time H_2 : M_2. (See Sample Inputs below for clarity.) He has decided to study for K consecutive minutes while he is up. What is t...
Solve the programming task below in a Python markdown code block. Given is a positive integer N. Find the number of pairs (A, B) of positive integers not greater than N that satisfy the following condition: * When A and B are written in base ten without leading zeros, the last digit of A is equal to the first digit o...
Solve the programming task below in a Python markdown code block. We have a sequence of N integers A~=~A_0,~A_1,~...,~A_{N - 1}. Let B be a sequence of K \times N integers obtained by concatenating K copies of A. For example, if A~=~1,~3,~2 and K~=~2, B~=~1,~3,~2,~1,~3,~2. Find the inversion number of B, modulo 10^9...
Solve the programming task below in a Python markdown code block. In some other world, today is the day before Christmas Eve. Mr. Takaha is buying N items at a department store. The regular price of the i-th item (1 \leq i \leq N) is p_i yen (the currency of Japan). He has a discount coupon, and can buy one item wit...
Solve the programming task below in a Python markdown code block. We have a permutation of the integers from 1 through N, p_1, p_2, .., p_N. We also have M pairs of two integers between 1 and N (inclusive), represented as (x_1,y_1), (x_2,y_2), .., (x_M,y_M). AtCoDeer the deer is going to perform the following operatio...
Solve the programming task below in a Python markdown code block. Snuke is buying a lamp. The light of the lamp can be adjusted to m levels of brightness, represented by integers from 1 through m, by the two buttons on the remote control. The first button is a "forward" button. When this button is pressed, the bright...
Solve the programming task below in a Python markdown code block. <image> There used to be a game called Joseph's potatoes. Let's say n people are participating. Participants form a circle facing the center and are numbered starting from 1. One hot potato is given to participant n (the large number 30 inside the fig...
Solve the programming task below in a Python markdown code block. At Aizu Riverside Hospital, inpatients walk twice a day for rehabilitation and health promotion. As the number of people trying to recover their physical strength by walking is increasing day by day in order to leave the hospital energetically, the dire...
Solve the programming task below in a Python markdown code block. Please find the greatest common divisor of two natural numbers. A clue is: The Euclid's algorithm is a way to resolve this task. Input The input file consists of several lines with pairs of two natural numbers in each line. The numbers do not exceed...
Solve the programming task below in a Python markdown code block. At 17:00, special agent Jack starts to escape from the enemy camp. There is a cliff in between the camp and the nearest safety zone. Jack has to climb the almost vertical cliff by stepping his feet on the blocks that cover the cliff. The cliff has slipp...
Solve the programming task below in a Python markdown code block. Mr. Yamada Springfield Tanaka was appointed as Deputy Deputy Director of the National Land Readjustment Business Bureau. Currently, his country is in the midst of a major land readjustment, and if this land readjustment can be completed smoothly, his pr...
Solve the programming task below in a Python markdown code block. For given two circles $c1$ and $c2$, print the coordinates of the cross points of them. Constraints * The given circle have at least one cross point and have different center coordinates. * $-10,000 \leq c1x, c1y, c2x, c2y \leq 10,000$ * $1 \leq c1r, ...
Solve the programming task below in a Python markdown code block. For a set $S$ of integers, perform a sequence of the following operations. Note that each value in $S$ must be unique. * insert($x$): Insert $x$ to $S$ and report the number of elements in $S$ after the operation. * find($x$): Report the number of $x$ ...
Solve the programming task below in a Python markdown code block. Rudolf is on his way to the castle. Before getting into the castle, the security staff asked him a question: Given two binary numbers a and b of length n. How many different ways of swapping two digits in a (only in a, not b) so that bitwise OR of thes...
Solve the programming task below in a Python markdown code block. This is an interactive problem. In the Wonderful Metropolis of the Future, there is no need in subway train drivers. Due to the technological progress, they were replaced by the Artificial Intelligence (AI). Unfortunately, one day the predictions of sc...
Solve the programming task below in a Python markdown code block. The Squareland national forest is divided into equal 1 × 1 square plots aligned with north-south and east-west directions. Each plot can be uniquely described by integer Cartesian coordinates (x, y) of its south-west corner. Three friends, Alice, Bob, ...
Solve the programming task below in a Python markdown code block. Salem gave you n sticks with integer positive lengths a_1, a_2, …, a_n. For every stick, you can change its length to any other positive integer length (that is, either shrink or stretch it). The cost of changing the stick's length from a to b is |a - ...
Solve the programming task below in a Python markdown code block. Berland SU holds yet another training contest for its students today. n students came, each of them brought his laptop. However, it turned out that everyone has forgot their chargers! Let students be numbered from 1 to n. Laptop of the i-th student has...
Solve the programming task below in a Python markdown code block. Let's define a function f(p) on a permutation p as follows. Let g_i be the [greatest common divisor (GCD)](https://en.wikipedia.org/wiki/Greatest_common_divisor) of elements p_1, p_2, ..., p_i (in other words, it is the GCD of the prefix of length i). T...
Solve the programming task below in a Python markdown code block. Kamil likes streaming the competitive programming videos. His MeTube channel has recently reached 100 million subscribers. In order to celebrate this, he posted a video with an interesting problem he couldn't solve yet. Can you help him? You're given a...
Solve the programming task below in a Python markdown code block. Recently, Norge found a string s = s_1 s_2 … s_n consisting of n lowercase Latin letters. As an exercise to improve his typing speed, he decided to type all substrings of the string s. Yes, all (n (n + 1))/(2) of them! A substring of s is a non-empty s...
Solve the programming task below in a Python markdown code block. You are given two integers a and m. Calculate the number of integers x such that 0 ≤ x < m and \gcd(a, m) = \gcd(a + x, m). Note: \gcd(a, b) is the greatest common divisor of a and b. Input The first line contains the single integer T (1 ≤ T ≤ 50) — ...
Solve the programming task below in a Python markdown code block. Nash designed an interesting yet simple board game where a player is simply required to follow instructions written on the cell where the player currently stands. This board game is played on the n× n board. Rows and columns of this board are numbered...
Solve the programming task below in a Python markdown code block. Having read half of the book called "Storm and Calm" on the IT lesson, Innocentius was absolutely determined to finish the book on the maths lessons. All was fine until the math teacher Ms. Watkins saw Innocentius reading fiction books instead of solvin...
Solve the programming task below in a Python markdown code block. Oleg's favorite subjects are History and Math, and his favorite branch of mathematics is division. To improve his division skills, Oleg came up with t pairs of integers p_i and q_i and for each pair decided to find the greatest integer x_i, such that: ...
Solve the programming task below in a Python markdown code block. Monocarp had a sequence a consisting of n + m integers a_1, a_2, ..., a_{n + m}. He painted the elements into two colors, red and blue; n elements were painted red, all other m elements were painted blue. After painting the elements, he has written two...
Solve the programming task below in a Python markdown code block. Cirno gave AquaMoon a chessboard of size 1 × n. Its cells are numbered with integers from 1 to n from left to right. In the beginning, some of the cells are occupied with at most one pawn, and other cells are unoccupied. In each operation, AquaMoon can...
Solve the programming task below in a Python markdown code block. In Berland the opposition is going to arrange mass walking on the boulevard. The boulevard consists of n tiles that are lain in a row and are numbered from 1 to n from right to left. The opposition should start walking on the tile number 1 and the finis...
Solve the programming task below in a Python markdown code block. One day n students come to the stadium. They want to play football, and for that they need to split into teams, the teams must have an equal number of people. We know that this group of people has archenemies. Each student has at most two archenemies. ...
Solve the programming task below in a Python markdown code block. n people came to a party. Then those, who had no friends among people at the party, left. Then those, who had exactly 1 friend among those who stayed, left as well. Then those, who had exactly 2, 3, ..., n - 1 friends among those who stayed by the momen...
Solve the programming task below in a Python markdown code block. One beautiful day Vasily the bear painted 2m circles of the same radius R on a coordinate plane. Circles with numbers from 1 to m had centers at points (2R - R, 0), (4R - R, 0), ..., (2Rm - R, 0), respectively. Circles with numbers from m + 1 to 2m had ...
Solve the programming task below in a Python markdown code block. Simon has a prime number x and an array of non-negative integers a1, a2, ..., an. Simon loves fractions very much. Today he wrote out number <image> on a piece of paper. After Simon led all fractions to a common denominator and summed them up, he got a...
Solve the programming task below in a Python markdown code block. Arthur and Alexander are number busters. Today they've got a competition. Arthur took a group of four integers a, b, w, x (0 ≤ b < w, 0 < x < w) and Alexander took integer с. Arthur and Alexander use distinct approaches to number bustings. Alexander i...
Solve the programming task below in a Python markdown code block. Let's call an undirected graph of n vertices p-interesting, if the following conditions fulfill: * the graph contains exactly 2n + p edges; * the graph doesn't contain self-loops and multiple edges; * for any integer k (1 ≤ k ≤ n), any subgrap...
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. You are given three strings (s1, s2, s3). For each integer l (1 ≤ l ≤ min(|s1|, |s2|, |s3|) you need to find how many triples (i1, i2, i3) exist such that three strings sk[ik... ik + l - 1] (k = 1, 2, 3) are pairwise equal. Print all found numbers modul...
Solve the programming task below in a Python markdown code block. You are given sequence a1, a2, ..., an and m queries lj, rj (1 ≤ lj ≤ rj ≤ n). For each query you need to print the minimum distance between such pair of elements ax and ay (x ≠ y), that: * both indexes of the elements lie within range [lj, rj], that...
Solve the programming task below in a Python markdown code block. Sasha and Ira are two best friends. But they aren’t just friends, they are software engineers and experts in artificial intelligence. They are developing an algorithm for two bots playing a two-player game. The game is cooperative and turn based. In eac...
Solve the programming task below in a Python markdown code block. Shapur was an extremely gifted student. He was great at everything including Combinatorics, Algebra, Number Theory, Geometry, Calculus, etc. He was not only smart but extraordinarily fast! He could manage to sum 1018 numbers in a single second. One day...
Solve the programming task below in a Python markdown code block. First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which someti...
Solve the programming task below in a Python markdown code block. One particularly well-known fact about zombies is that they move and think terribly slowly. While we still don't know why their movements are so sluggish, the problem of laggy thinking has been recently resolved. It turns out that the reason is not (as ...
Solve the programming task below in a Python markdown code block. Anton is playing a very interesting computer game, but now he is stuck at one of the levels. To pass to the next level he has to prepare n potions. Anton has a special kettle, that can prepare one potions in x seconds. Also, he knows spells of two type...
Solve the programming task below in a Python markdown code block. On the Literature lesson Sergei noticed an awful injustice, it seems that some students are asked more often than others. Seating in the class looks like a rectangle, where n rows with m pupils in each. The teacher asks pupils in the following order:...
Solve the programming task below in a Python markdown code block. The year of 2012 is coming... According to an ancient choradrican legend in this very year, in 2012, Diablo and his brothers Mephisto and Baal will escape from hell, and innumerable hordes of demons will enslave the human world. But seven brave heroes ...
Solve the programming task below in a Python markdown code block. Wherever the destination is, whoever we meet, let's render this song together. On a Cartesian coordinate plane lies a rectangular stage of size w × h, represented by a rectangle with corners (0, 0), (w, 0), (w, h) and (0, h). It can be seen that no col...
Solve the programming task below in a Python markdown code block. You are given several queries. In the i-th query you are given a single positive integer ni. You are to represent ni as a sum of maximum possible number of composite summands and print this maximum number, or print -1, if there are no such splittings. ...
Solve the programming task below in a Python markdown code block. Vasya has a non-negative integer n. He wants to round it to nearest integer, which ends up with 0. If n already ends up with 0, Vasya considers it already rounded. For example, if n = 4722 answer is 4720. If n = 5 Vasya can round it to 0 or to 10. Both...
Solve the programming task below in a Python markdown code block. We consider a positive integer perfect, if and only if the sum of its digits is exactly 10. Given a positive integer k, your task is to find the k-th smallest perfect positive integer. Input A single line with a positive integer k (1 ≤ k ≤ 10 000). O...
Solve the programming task below in a Python markdown code block. You are given a sequence a consisting of n integers. You may partition this sequence into two sequences b and c in such a way that every element belongs exactly to one of these sequences. Let B be the sum of elements belonging to b, and C be the sum o...
Solve the programming task below in a Python markdown code block. Petya loves volleyball very much. One day he was running late for a volleyball match. Petya hasn't bought his own car yet, that's why he had to take a taxi. The city has n junctions, some of which are connected by two-way roads. The length of each road ...
Solve the programming task below in a Python markdown code block. Two participants are each given a pair of distinct numbers from 1 to 9 such that there's exactly one number that is present in both pairs. They want to figure out the number that matches by using a communication channel you have access to without reveal...
Solve the programming task below in a Python markdown code block. Valentine week has started and Chotu wants to impress his crush. On this rose day Chotu plans to give his crush a bouquet of roses. Chotu visits a rose shop which has N number of roses and each rose has a certain love factor. Now Chotu wants to make a b...
Solve the programming task below in a Python markdown code block. Statement: Security is the major factor, which is prohibiting hackers letting into bank accounts online. But still, we have breached 2nd level security of SBIS bank and a final level is kept for you. Your task is simple, we are receiving an integer toke...
Solve the programming task below in a Python markdown code block. Alice and Bob text each other everyday. Bob, tired of writing long messages has come up with a way to reduce their size. Alice and Bob are both fluent in 2 languages, L1 and L2. A language consists of a collection of distinct words, where each word cons...
Solve the programming task below in a Python markdown code block. Given is a string S consisting of `0` and `1`. Find the number of strings, modulo 998244353, that can result from applying the following operation on S zero or more times: * Remove the two characters at the beginning of S, erase one of them, and reinse...
Solve the programming task below in a Python markdown code block. There are N people living on a number line. The i-th person lives at coordinate X_i. You are going to hold a meeting that all N people have to attend. The meeting can be held at any integer coordinate. If you choose to hold the meeting at coordinate ...
Solve the programming task below in a Python markdown code block. We have N ID cards, and there are M gates. We can pass the i-th gate if we have one of the following ID cards: the L_i-th, (L_i+1)-th, ..., and R_i-th ID cards. How many of the ID cards allow us to pass all the gates alone? Constraints * All values ...
Solve the programming task below in a Python markdown code block. Find the number of integers between 1 and K (inclusive) satisfying the following condition, modulo 10^9 + 7: * The sum of the digits in base ten is a multiple of D. Constraints * All values in input are integers. * 1 \leq K < 10^{10000} * 1 \leq D \l...
Solve the programming task below in a Python markdown code block. You are given a string S consisting of `0` and `1`. Find the maximum integer K not greater than |S| such that we can turn all the characters of S into `0` by repeating the following operation some number of times. * Choose a contiguous segment [l,r] in...