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We are given a collection of booking requests, where each request represents a group of guests who either all get seated together or do not come at all.

The problem presents a binary tree where leaf nodes represent boolean values 0 (false) or 1 (true), and internal nodes represent boolean operations OR, AND, XOR, and NOT, encoded as integers 2, 3, 4, and 5. You are also given a target boolean result.

The problem gives us a binary string s, which means the string contains only the characters '0' and '1'. We need to find the length of the longest substring that is considered balanced. A substring is balanced when two conditions are satisfied: 1.

This problem asks us to analyze sales data to determine which products each user spent the most money on. We are given two tables: Sales and Product. The Sales table contains individual transactions, showing which user bought which product and in what quantity.

The problem asks us to find, for each index in a given array nums, the length of the shortest contiguous subarray starting at that index whose bitwise OR is equal to the maximum possible bitwise OR obtainable from that index onward.

We are given an integer array nums, and we want to count how many ways we can split it into exactly three non-empty contiguous subarrays: - nums1 - nums2 - nums3 such that: where + means concatenation. A split is considered beautiful if at least one of these conditions holds: 1.

This problem asks us to find the last day we can cross a grid from the top row to the bottom row, walking only on land. The grid is initially all land (0), and each day, specific cells are flooded with water (1) according to the cells array.

We are given a set of points on the plane representing the crystals that survived after part of a symmetric snowflake melted.

The problem is about scheduling meetings into a fixed number of rooms, where each meeting has a unique start time and a defined duration. We have n rooms numbered from 0 to n - 1, and we are given a list of meetings represented as [start, end) intervals.

The problem asks us to compute the largest three distinct rhombus sums in a given m x n integer grid. A rhombus in this context is a square rotated 45 degrees, whose corners align with grid cells. The rhombus sum includes only the border cells of this shape, not the interior.

The problem asks us to compute the triangular sum of an array of digits. The triangular sum is obtained by repeatedly reducing the array according to a simple rule: for every pair of adjacent elements, sum them modulo 10 to form a new array of length one less than the current…

We are asked to count the numbers in a given interval [l, r] where the first digit equals the last digit. The input consists of two integers l and r, defining the interval. The output is a single integer, the count of numbers satisfying this property.

This problem involves simulating passengers arriving at a bus station and boarding buses as they arrive. We are given two tables: Buses and Passengers. Each bus has a unique busid and an arrivaltime, and each passenger has a unique passengerid and an arrivaltime.

The problem gives us a three digit integer n. We must determine whether n is a fascinating number. A number is considered fascinating when we concatenate three values together: 1. n 2. 2 n 3.

The problem describes a street represented by positions from 0 to n - 1. There are multiple street lamps, each defined by its position and range. A lamp at position p with range r illuminates all positions from max(0, p - r) to min(n - 1, p + r), inclusive.

We are asked to determine the earliest square where the opposition can hold a demonstration given the interference of the city administration. There are n squares arranged by increasing distance from the city center, with square 1 being the most central.

The problem gives us a square matrix grid of size n x n, where every element is an integer. We need to count how many (row, column) pairs are exactly equal.

The problem presents an array nums of length n that is a permutation of integers from 0 to n - 1. We are asked to find a permutation perm of the same range [0, 1, 2, ...

We have a rectangular board where every cell contains one of three symbols. A move selects an active cell and disables cells along diagonals passing through it. The exact diagonals depend on the symbol. A cell marked L attacks the two diagonals with constant i + j.

We are given one long string that originally consisted of several file names written back to back with no separators. Every valid file name must look like name.ext. The rules are strict. The part before the dot contains only lowercase letters and has length from 1 to 8.

The problem provides two relational tables, one named Employees and another named Salaries, both keyed by employeeid. Each employee may or may not appear in both tables. The Employees table contains the employee’s name, while the Salaries table contains the employee’s salary.

The problem asks us to construct a polynomial equation from a database table called Terms. Each row in the table represents a single term in the equation, where power is the exponent of X and factor is the coefficient.

The problem asks us to determine how many possible sequences of integers exist that match a given array of differences between consecutive elements, while staying within a specified inclusive range.

We are given a single integer and must decide whether it satisfies a very specific prime property. A number is considered truncatable if every suffix formed by repeatedly removing the leftmost digit is still prime.

The problem asks for the minimum number of straight cuts required to divide a circle into n equal slices. A valid cut can either pass through the center and touch two points on the circle, or touch one point on the circle and pass through the center.

The problem gives us a collection of 2D points, where each point is represented as (xi, yi). We must cover every point using a set of rectangles. Each rectangle has a very special form: - Its bottom edge always lies on the x-axis, meaning the rectangle starts at y = 0.

The Friends table represents an undirected friendship graph. Each row (userid1, userid2) means the two users are directly connected as friends. The problem asks us to find every friendship pair where the two users do not share any common friend.

The problem gives us an array nums containing positive integers. In a single operation, we are allowed to remove either: - Exactly 2 equal elements, or - Exactly 3 equal elements. Our goal is to remove all elements from the array using the minimum possible number of operations.

We are given an array usageLimits where usageLimits[i] tells us how many times the number i can be used across all groups. The numbers available are exactly 0 through n - 1, where n is the length of the array.

We are asked to manipulate dates by adding or subtracting a number of days. The input consists of a date string in the "DD.MM.YYYY" format and an integer representing a shift in days, which can be positive or negative.

We are given the final standings of a programming contest. The scores are already sorted in non-increasing order, meaning each participant has a score greater than or equal to the next participant. A participant advances to the next round if two conditions are true.

We are given a string consisting solely of the characters "x" and "y". Two operations can be applied repeatedly in a specific order. The first operation swaps a consecutive "y" followed by "x" into "x" then "y". The second operation removes a consecutive "x" followed by "y".

The problem asks us to determine the minimum number of characters to take from either end of a string s consisting only of the letters 'a', 'b', and 'c' so that we collect at least k of each character.

This problem asks us to implement a function similar to JavaScript's Promise.allSettled(), but without actually using the built-in method. We are given an array of functions functions, where each function, when invoked, returns a promise.

The task is to determine how many trailing zeros appear at the end of the factorial of a given integer n. A factorial, denoted n!, is the product of all integers from 1 up to n.

Vasya scribbled an Internet address in his notebook, but he was in a hurry and omitted all punctuation characters like :, /, and ..

We are given a line of numbered chests, each containing some number of coins. On each move, a player chooses an integer position $x$, and that move simultaneously affects three specific chests: $x$, $2x$, and $2x+1$. From each of these chests, one coin is removed if it exists.

The problem asks us to compute a ranking of students based on textual feedback they receive. We are given two lists of words: positivefeedback and negativefeedback.

The problem asks us to count how many integers lie between two given numeric strings num1 and num2 (inclusive) such that the sum of their digits is between minsum and maxsum.

We have a two-player game played with two numbers on a blackboard, call them a and b. Each player can, on their turn, either replace the larger number with the remainder of dividing it by the smaller number, or subtract a positive multiple of the smaller number from the larger…

This problem models a garbage collection system with three separate garbage trucks: - One truck collects metal garbage, represented by 'M' - One truck collects paper garbage, represented by 'P' - One truck collects glass garbage, represented by 'G' The input array garbage…

We are given a single formatted string that represents a set of lowercase English letters. The set is written in a very specific textual form: it starts with an opening brace, ends with a closing brace, and inside the braces letters are listed separated by comma and space.

This problem asks us to transform a given string s into another string t such that the total transformation cost does not exceed k. Among all possible valid strings, we must return the lexicographically smallest one. The key detail is how the transformation cost is defined.

The problem is asking us to compute the total number of distinct sequences of dice rolls of length n that satisfy two constraints: the greatest common divisor (GCD) of any two consecutive rolls must be 1, and any repeated value in the sequence must be separated by at least two…

We are asked to partition a club of members into groups based on responsibility and age constraints. Each member has a responsibility value and an age.

The problem is asking us to implement a food rating system that supports dynamic updates to the ratings of individual food items and allows querying for the highest-rated food for a given cuisine.

We are given an array nums, and we must consider all non-empty subsequences of that array. A subsequence preserves the original order of elements, but elements do not need to be contiguous.

The infinite string in this problem is built recursively. Start with: In general: The alphabet contains 36 symbols: The full string after 30 steps has length: $ For k = 30, the length is about 10^9, which matches the input bounds.

The problem gives us an integer array nums and an integer k. For every contiguous subarray of length k, we must determine how many unique values appear inside that window. A subarray is a continuous portion of the array.

The problem is asking us to compute a special sum over a given array nums by repeatedly concatenating the first and last elements of the array until it is empty.

The contest platform numbers every round consecutively by start time. A round can either be a standalone Div2 round, or a pair of simultaneous rounds where Div2 gets identifier i and Div1 gets identifier i + 1. Sereja only participates in Div2 rounds.

The problem gives us an undirected graph with n vertices labeled from 0 to n - 1. The graph is represented using an edge list, where each edge connects two vertices in both directions. Our task is to find the length of the shortest cycle in the graph.

The problem asks us to construct the lexicographically smallest number from a string pattern consisting of 'I' and 'D'.

The problem asks us to find the length of the longest subarray within a given array nums such that the bitwise AND of all elements in that subarray is maximized.

The problem gives us a positive integer n and asks us to find a special integer x, called the pivot integer, such that: - The sum of all integers from 1 to x is equal to - The sum of all integers from x to n The important detail is that x belongs to both sums.

This guide will be very long, likely exceeding a single message cleanly while still maintaining the level of detail and formatting quality you requested for a reference document.

The game consists of n questions, each with some base value a[i]. Some questions are marked as auctions. Team R2 starts by choosing the first question. After that, whoever answered the previous question correctly gets to choose the next question.

This problem gives us a weighted directed graph with n nodes and a list of directed edges. Each edge has a positive weight. We are also given two source nodes, src1 and src2, along with a destination node dest.

The problem requires identifying the largest "good" integer from a given string of digits. A "good" integer is defined as a substring of length 3 where all digits are identical.

We are given a long strip of vertical planks, each with a fixed height. For any contiguous segment of planks of fixed length $k$, Vasya paints a rectangle whose height is determined by the shortest plank inside that segment.

The problem asks us to implement a custom string encryption algorithm. We are given a string s and an integer k. For each character in s, we need to replace it with the character that is k positions ahead in the string, in a cyclic manner.

The problem asks us to compute a special value called the x-sum for every contiguous subarray of length k. For each window of size k, we first count how many times each number appears. After that, we only keep the contributions of the top x most frequent distinct values.

We are given a permutation of numbers from 1 to n. For every query interval [l, r], we must count how many ordered pairs of positions (q, w) inside that interval satisfy: $$p[q] mid p[w]$$ Since all values are distinct and form a permutation, every number appears exactly once.

The problem is asking for the maximum length of a substring in a given string s such that no character occurs more than twice within that substring. In other words, for any valid substring, each character can appear at most two times.

This problem asks us to double a number represented as a singly linked list. Each node of the list contains a single digit, and the digits are stored in the order from most significant to least significant. For example, the list [1,8,9] represents the number 189.

We are given a directed graph where every node represents a program state. Each state does one of three things to a variable: 0 means the variable is ignored. 1 means the variable is assigned a new value. 2 means the variable is used.

The problem gives us a binary string s, containing only '0' and '1' characters. We are allowed to rearrange the bits in any order we want, but we must use exactly the same bits that appear in the original string.

The problem asks us to determine the latest time we can arrive at a bus station to catch a bus, given the departure times of buses, arrival times of other passengers, and the maximum capacity of each bus.

The problem asks us to design a mutable tree-based data structure that supports three operations: lock, unlock, and upgrade. Each node in the tree may either be unlocked or locked by exactly one user. The operations must follow strict rules about when a node may change state.

The problem asks us to implement a memoized version of a given function fn. A memoized function is one that caches the results of previous calls and returns the cached result if the same inputs are passed again.

The problem gives us an array of positive integers and asks us to choose the largest possible subset that can be rearranged into a very specific symmetric structure. The required structure looks like this: where is a power of two.

We are given an n × n board where every cell contains an integer. For each cell, we compare two quantities. The first quantity is the sum of all numbers in that cell’s row. The second quantity is the sum of all numbers in that cell’s column.

The problem asks us to select a number from an array of distinct positive integers such that the chosen number is neither the minimum nor the maximum in the array. In other words, we must return a number that lies strictly between the smallest and largest elements.

This problem asks us to distribute a set of integers into numbered slots in a way that maximizes a scoring function based on bitwise AND operations.

We are given a set of distinct points on a 2D plane. The task is to count how many unordered triples of points form a configuration where one point lies exactly at the midpoint of the segment formed by the other two.

We are given a valid parenthesis sequence. Every opening bracket has a unique matching closing bracket, and the pairs are properly nested. We want to assign colors to brackets under two rules.

LeetCode 2539: Count the Number of Good Subsequences (Medium)

This problem asks us to find the smallest non-empty contiguous subarray whose bitwise OR is at least k. The input consists of: - An integer array nums - An integer k For any subarray nums[left:right+1], we compute the bitwise OR of all elements inside that range.

The problem asks us to find the largest-valued odd integer substring from a given string num that represents a large integer. Here, a substring is any contiguous sequence of characters in num.

The problem asks us to determine the kth smallest amount that can be formed using coins of given denominations under a strict limitation: we can only use a single type of coin at a time. In other words, combinations of different denominations are not allowed.

The problem gives us a 50 x 50 chessboard containing exactly one knight and up to 15 pawns. The knight starts at position (kx, ky), and every pawn is placed at one of the coordinates in positions. Two players, Alice and Bob, alternate turns. Alice moves first.

The problem gives us two arrays, nums1 and nums2, where each array contains unique digits from 1 to 9. We need to construct the smallest possible number such that the number contains at least one digit from each array.

The problem gives us a string s containing only lowercase English letters. We are allowed to perform operations where we change any single character into any other lowercase character.

The problem asks us to design a data structure that supports two operations efficiently: 1. Assign a number to a given index. 2. Find the smallest index currently assigned to a given number.

We are asked to determine how many generals need warm blankets at a rectangular table placed on an infinite Cartesian plane. The table corners are given by two points with integer coordinates, and each integer point along the perimeter of the rectangle hosts a general.

The problem asks us to count how many pairs of indices (i, j) satisfy two conditions: 1. i < j 2. The sum nums[i] + nums[j] lies within the inclusive range [lower, upper] We are given an integer array nums and two bounds, lower and upper.

This problem asks us to determine how long we can safely wait before starting to move from the top-left corner of a grid to the bottom-right corner while a fire spreads across the grid over time.

We are given a collection of distinct points on a 2D plane. Each point is represented as (x, y). An increasing path is a sequence of points where both coordinates strictly increase from one point to the next.

The problem asks us to transform an integer array so that its median becomes exactly k, using the minimum number of operations. In one operation, we may either increase or decrease any single element by 1. The median is defined after sorting the array in non-decreasing order.

The problem asks us to take a JSON-formatted string str and convert it into the equivalent native data structure.

The problem gives us an integer array nums containing exactly three types of elements: 1. n - 2 special numbers 2. One element equal to the sum of all special numbers 3. One outlier The task is to return the largest possible value that could serve as the outlier.

The problem gives us an integer array nums and asks us to find the length of the longest contiguous subarray that is either strictly increasing or strictly decreasing. A subarray must consist of consecutive elements from the original array.

We have a large circular table with radius R and want to place n identical circular plates, each with radius r. Every plate must satisfy three conditions simultaneously. First, the entire plate must stay inside the table. Second, every plate must touch the boundary of the table.

Lesha has a problem description made of n distinct words, written in a fixed order. Each archive problem is another sequence of words, but archive descriptions may repeat words many times. We want to compare Lesha’s description against every archive description.

The problem asks us to transform a given integer array nums into a non-decreasing array by performing a sequence of operations. In each operation, we are allowed to replace any single element with any two elements that sum to it.

The problem asks us to calculate the total appeal of all substrings of a given string s. The appeal of a string is defined as the number of distinct characters it contains.

The problem asks us to find the length of the longest subsequence in an integer array nums such that the subsequence is strictly increasing and the difference between consecutive elements does not exceed a given integer k.

The problem asks us to compute the minimum number of adjacent swaps needed to transform a given number num into the kth smallest wonderful integer. A wonderful integer is any permutation of num's digits that is strictly greater than num.

The problem gives us a 0-indexed integer array nums, and we must count how many triplets (i, j, k) satisfy two conditions.

We are given a lowercase string and must choose some characters, in order, to form a subsequence that is both a palindrome and lexicographically as large as possible. A subsequence does not need to stay contiguous.