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We are given an integer array flowers, where each element represents the beauty value of a flower in a line. We may remove any flowers we want, while preserving the relative order of the remaining flowers. After removals, the remaining sequence must form a valid garden.

We are given a flag represented as an _n_×_m_ grid where each cell is painted with one of 26 colours labeled a to z. The goal is to repaint as few squares as possible so that two conditions hold. First, each row can use at most two different colours.

We are given an array of positive integers, and we want to sort it in non-decreasing order. The twist is that we can only swap elements if at least one of the two numbers involved is lucky. A lucky number is defined as a number containing only the digits 4 and 7.

We are given several short DNA fragments over the alphabet {A, C, G, T}. A longer DNA string is considered valid if every position of the string belongs to at least one occurrence of one of the given fragments. The fragments may overlap arbitrarily.

The problem gives an array nums where each value represents the maximum distance you can jump forward from that position. You start at index 0, and your goal is to reach the final index using the minimum number of jumps possible.

We have a row of n lamps, each initially either on or off. Each lamp has a number from 1 to n. We also have n keys numbered the same way. Pressing key i toggles every lamp whose number is divisible by i.

We are given a single integer n, and we need to construct the smallest positive integer whose number of divisors is exactly n.

The problem asks us to construct a maximum binary tree from a given integer array nums with unique elements. A maximum binary tree is a binary tree where each node is the maximum element of the subarray it represents.

This problem asks us to count how many subsets of crimes satisfy two constraints simultaneously: 1. The total number of members used is at most n 2.

The problem gives us a list of directory descriptions, where each string represents a directory and the files inside it. Each file entry includes both the filename and its content. For example: means: - The directory path is root/a - Inside this directory: - 1.

The problem asks us to compute, for every element in the array, how many elements to its right are strictly smaller than it. Given an array nums, we must return another array counts of the same length.

The problem asks us to compute the total number of unique characters across every possible substring of a given string. A character is considered unique inside a substring if it appears exactly once within that substring.

The problem is asking us to identify all playback sessions during which no advertisements were shown. We are given two tables: Playback and Ads. The Playback table lists sessions for each customer, with the start and end times of each session.

The problem gives us a string s that contains lowercase English letters and numerical digits. Our task is to find the second largest distinct digit that appears anywhere in the string. The important detail is that we care about distinct digits, not frequency.

The problem gives us a 2D integer matrix called grid and an integer x. In one operation, we may either add x to a cell or subtract x from a cell. Our goal is to make every value in the grid equal using the minimum number of operations.

The problem asks us to determine whether an integer array forms a perfect sequence of consecutive numbers without gaps o

The problem asks us to check whether all 1s in a given binary array nums are separated by at least k positions. In other

The problem gives us a binary string s, meaning the string contains only the characters '0' and '1'. We must split this string into two non-empty parts, a left substring and a right substring.

The problem gives us an integer array nums and an integer k. We are allowed to split the array into at most k contiguous, non-empty subarrays. For each subarray, we compute its average, then sum all of those averages together. Our goal is to maximize that total score.

We are asked to find the cheapest way for Gerald to buy three pieces of clothing that all match each other. Each clothing item has a price, and some pairs of items are marked as matching. The input gives us the total number of items, the prices, and a list of matching pairs.

The problem is asking us to identify the minimum set of vertices in a directed acyclic graph (DAG) such that starting from any of these vertices, all other nodes in the graph are reachable.

Let's dive into a full, detailed technical solution guide for LeetCode 959 - Regions Cut By Slashes following your formatting rules. The problem gives us an n x n grid where each cell contains either a forward slash '/', a backslash '', or a blank space ' '.

This problem asks us to simulate movement on a 2D plane according to a string of directional instructions. Each characte

The problem gives us an array called encoded, which was generated from an unknown permutation array perm. A permutation of the first n positive integers means the array contains every integer from 1 to n exactly once. For example: - [1,2,3] is a valid permutation of 1..

The problem is a two-player game played on a binary tree, where each player colors nodes starting from an initial chosen node. Player 1 picks a node x and colors it red, while Player 2 picks a different node y and colors it blue.

Vasya is at the central station of a subway branch with two endpoints. Each endpoint corresponds to one of his girlfriends: Dasha or Masha. Trains to Dasha’s station arrive every a minutes and trains to Masha’s station arrive every b minutes.

This problem simulates a school cafeteria where students line up to take sandwiches from a stack. Each student has a preference for either a circular sandwich (0) or a square sandwich (1).

This problem asks whether a linked list appears as a continuous downward path inside a binary tree. The path does not ne

We have three cups arranged in a line, and a ball starts under one of them. The performer performs exactly three swaps. Each swap exchanges the positions of two cups. After all swaps finish, we must determine which cup contains the ball.

The problem gives us an array of integer pairs, where each pair represents an interval-like relationship of the form [left, right]. Every pair satisfies the condition left < right. We want to build the longest possible chain of pairs.

Here is a comprehensive solution guide for LeetCode 1340 following your requested format. The problem presents an array

The problem presents an m x n matrix called grid where each element is a character representing either a wall 'W', an enemy 'E', or an empty cell '0'. The task is to determine the maximum number of enemies that can be eliminated by placing a single bomb in an empty cell.

The task is to decompose a given integer n into its prime factors and print them in non-decreasing order, with each prime repeated according to its multiplicity. Essentially, if a number is a product of primes like $n = 2^2 cdot 3^1 cdot 5^2$, the output should be 2 2 3 5 5.

This problem is a variant of the classic number guessing game with a twist: incorrect guesses cost money equal to the value guessed, and the goal is to minimize the maximum cost required to guarantee a win.

The problem presents an m x n matrix M initialized with all zeros. You are also given an array of operations ops, where each operation ops[i] = [ai, bi] instructs you to increment by one all elements in the submatrix defined by the top-left corner (0,0) and the bottom-right…

The problem is asking us to reconstruct a binary tree given two traversal orders: preorder and inorder. In a preorder traversal, nodes are visited in the order: root, left subtree, right subtree.

The problem gives us a directed graph with n nodes labeled from 0 to n - 1. Every edge in the graph has a color, either red or blue.

This problem asks us to identify all buyers who purchased the product named S8 but never purchased the product named iPhone. We are given two tables: The Product table stores information about products. Each row contains a unique productid, the product name, and its unit price.

The problem asks us to determine whether a given string s can be split into exactly three non-empty substrings, each of which is a palindrome. A palindrome is a string that reads the same forward and backward. For example, the string "aba" is a palindrome, whereas "abc" is not.

We are given a string and we consider every palindromic substring inside it. Each occurrence matters separately, even if two substrings have the same text. For example, in "aaa" there are three different occurrences of "a".

The problem asks us to compute a clumsy factorial for a given positive integer n. A standard factorial multiplies all integers from n down to 1, but the clumsy factorial modifies the operations: instead of multiplying all numbers, it cycles through '', '/', '+', and '-' in…

This problem asks us to determine whether one binary tree appears as an exact subtree inside another binary tree.

We have an undirected graph where every road has two thresholds attached to it. For a road with values (g, s), the road becomes safe only if the king gives at least g gold coins and at least s silver coins to the bandits.

The problem gives us a string s and two scoring rules: - Removing the substring "ab" earns x points. - Removing the substring "ba" earns y points. We may perform these removals as many times as possible, in any order we choose.

We are given a string representing a simple arithmetic expression of the form a+b=c, where a, b, and c are integers.

The problem is a variant of the classic "Sokoban" puzzle. You are given a grid representing a warehouse, where a player

This problem models how functions execute on a single-threaded CPU. Since the CPU is single-threaded, only one function can actively execute at any given moment. However, functions may call other functions, including recursive calls to themselves.

The problem asks us to find the substring of a given string s that is lexicographically largest among all possible substrings. A substring is any contiguous portion of the string.

The problem is asking us to simulate a single-tab browser with a history mechanism. You start on a homepage, and from there, you can visit new URLs, backtrack a certain number of steps, or forward a certain number of steps.

The problem gives us a binary array called flowerbed, where: - 0 represents an empty plot - 1 represents a plot that already contains a flower We are also given an integer n, which represents how many new flowers we want to plant.

The problem is asking us to completely cover a rectangle of size n x m with the fewest number of squares that have integer side lengths. The rectangle can be tiled with squares of any size, as long as each square fits entirely within the rectangle and there is no overlap.

We have n independent logs, each with length m. On a move, a player chooses one existing log and splits it into several equal pieces. If a log of length x is split into t equal parts, then t 1, t must divide x, and every resulting part must have length at least k.

Each person points to exactly one other person. If someone learns the news, they call the person they point to, who then calls the next person, and so on. We may add extra directed edges of the form x -> y, meaning person x must also call y.

Here is a complete, detailed technical solution guide for LeetCode 1673 - Find the Most Competitive Subsequence followin

The problem models a recursive elimination game played on a row of colored balls. The board is represented as a string where each character corresponds to a colored ball. The available colors are 'R', 'Y', 'B', 'G', and 'W'.

The problem asks us to repeatedly remove groups of exactly k adjacent identical characters from a string until no more such groups exist. A removal operation works as follows: - Find k consecutive characters that are all the same. - Remove those characters from the string.

This problem asks us to determine the maximum profit that can be made from a single stock transaction. A transaction consists of buying one stock on one day and selling it on a later day. The key restriction is that the selling day must come after the buying day.

The problem gives us two strings, start and result, both consisting only of the characters 'L', 'R', and 'X'. We are allowed to transform the start string using only two kinds of moves: - Replace "XL" with "LX" - Replace "RX" with "XR" The goal is to determine whether it is…

The problem requires classifying triangles based on the lengths of their three sides, represented by the columns A, B, a

The problem asks us to find the digit that appears at position n in an infinitely long sequence formed by concatenating all positive integers together.

This problem requires designing a specialized stack data structure, called CustomStack, that not only supports the usual

The problem asks us to process a string s that contains bracketed keys like (name) or (age) and replace them with corres

We are given a lowercase string and must find the substring that appears the largest number of times inside it. Occurrences may overlap. Among all substrings with the same maximum frequency, we choose the longest one.

We are given up to 200 distinct lowercase words. For every word, we must choose a short abbreviation whose length is between 1 and 4 characters, and whose characters appear in the original word in the same order.

The problem gives us an array called coins, where each element represents a coin denomination, and an integer called amount, which represents the target sum we want to construct. Our goal is to determine the minimum number of coins needed to make exactly amount.

We are given a digital time in HH:MM format and need to determine how far the analog clock hands must rotate from the initial position 12:00. The clock starts with both hands pointing at 12. We may rotate each hand independently, and only in the clockwise direction.

The problem asks us to generate every strobogrammatic number of a given length n. A strobogrammatic number is a number that still appears valid after being rotated 180 degrees. Not every digit works under rotation.

This problem asks us to determine which key on a keypad was pressed for the longest duration during a test sequence. We

The problem asks us to find the integral coordinate on a 2D plane where the network quality is maximized. We are given s

The problem asks us to find the longest substring that is both a prefix and a suffix of the given string s, while also e

This problem asks us to merge two already sorted singly linked lists into one new sorted linked list. The important detail is that we are not creating entirely new nodes for the merged result. Instead, we reuse the existing nodes by reconnecting their next pointers.

Nick wants to list all numbers of a given length n in base b, where digits range from 0 to b-1, but numbers cannot start with 0. Each page in his notepad holds exactly c numbers. We are asked to compute how many numbers appear on the last page he fills.

The problem asks us to repeatedly transform a number by summing its digits until only a single digit remains. The final single digit should then be returned. For example, if the input is 38, we first compute 3 + 8 = 11.

This problem asks us to process a sorted singly linked list and remove every value that appears more than once. The important distinction is that we are not keeping one copy of duplicated values. Instead, every node containing a duplicated value must be removed entirely.

The problem describes a single-row keyboard where each key is positioned at a unique index from 0 to 25. You are given a string keyboard of length 26 that specifies the layout of all lowercase English letters.

The problem asks us to determine whether a given positive integer num is a perfect square without using built in square root functions such as sqrt(). A perfect square is a number that can be written as: where k is an integer.

We are given a chess position containing exactly four pieces on a standard 8×8 board. White has two rooks and one king, black has only a king. The position is already legal, meaning no two pieces share a square and the two kings are not adjacent.

The problem asks us to design a data structure that continuously tracks the kth largest element in a stream of integers. We are given an integer k and an initial list of numbers called nums. After initialization, new numbers are added one at a time using the add method.

We are given a binary grid. A valid object is not a filled square, it is only the border of a square drawn with 1s. Every cell not belonging to the border must be 0.

We are asked to divide an island into connected territories for multiple parties. The island is represented by two rectangles placed side by side: one of size a by b and another of size c by d.

The problem asks us to compute minimal unique abbreviations for an array of distinct strings. An abbreviation replaces the middle characters of a word with a count, keeping the first and last characters.

We are given a valid binary search tree where every internal node has exactly two children. Each node stores a unique key. We are also given several query keys that are guaranteed not to appear in the tree. A normal BST search starts at the root.

This problem asks us to determine whether two singly linked lists share a common node, and if they do, return the exact node where the intersection begins. The important detail is that an intersection is based on node reference, not node value.

The problem asks us to determine the minimum number of swaps needed to transform one string into another, where both strings are anagrams of each other. A single operation consists of swapping any two characters in s1.

This problem asks us to swap the seat IDs of every two consecutive students in a classroom. The input is a table called Seat with two columns: id, which is a unique integer representing the seat number, and student, which is a string representing the student's name.

The garden is represented as an n × m grid. Each cell contains either 0 or 1. A 1 means there is a tree in that square, while 0 means the square is empty.

The problem gives us a collection of tokens, where each token has a numeric value. We also start with an initial amount of power and an initial score of 0. Every token can be used at most once, and each token can be played in exactly one of two ways.

The problem gives us an m x n binary matrix, where every element is either 0 or 1. We are allowed to choose any set of columns and flip them. Flipping a column means changing every 0 in that column to 1, and every 1 to 0.

In this problem, we are given a two dimensional grid of characters called board and a target string called word. The task is to determine whether the word can be formed by traversing the grid under a strict set of movement rules.

The problem gives us an array called colors, where each position contains one of three possible values: 1, 2, or 3. Each value represents a color assigned to that index. We are also given a list of queries.

Edit This problem gives us a permutation array arr containing integers from 1 to n, where n is the size of the binary st

The problem gives an array stones representing positions of stones on the X-axis, where each position is unique. The goal is to move the endpoint stones-the stones at the smallest and largest positions-so that eventually all stones occupy consecutive positions on the X-axis.

The task is to generate a multiplication table for numbers in a positional numeral system with a base k. Unlike the decimal system, the digits in this system range from 0 up to k-1. Petya wants to see products of numbers from 1 to k-1 expressed in this system.

We are asked to count the number of ways an arithmetic expression can be made unambiguous with parentheses so that, if all parentheses are removed, the expression is exactly the string given in the input.

The problem is asking us to take an existing m x n matrix and "reshape" it into a new matrix with r rows and c columns. Reshaping means rearranging the elements in the matrix in row-major order (left-to-right, top-to-bottom) without changing the order of the elements themselves.

The problem gives us a list of intervals, where each interval is represented as [li, ri], corresponding to the half open

The problem asks us to transform a given binary matrix mat into a zero matrix, where all elements are 0. Each operation

The problem asks us to simulate building a sorted array incrementally. We process the instructions array from left to ri

The problem asks us to compute the power of a string. The power is defined as the length of the longest contiguous subst

The problem gives us a string representation of a file system hierarchy. Every line represents either a directory or a file. The hierarchy is encoded using newline characters (n) to separate entries and tab characters (t) to indicate nesting depth.