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The problem describes a circular route containing n gas stations. At each station i, you can collect gas[i] units of fuel. Traveling from station i to station (i + 1) % n consumes cost[i] units of fuel.

The problem gives us a string s containing only lowercase English letters. We repeatedly look for two adjacent characters that are equal, remove both of them, and continue this process until no such adjacent duplicate pair exists.

The problem is asking us to solve a linear equation containing a single variable 'x' and integer coefficients, expressed as a string. The equation may include addition '+', subtraction '-', and the equality operator '='.

This problem asks us to traverse a binary tree and identify every node that is considered "lonely". A node is lonely if

We are asked to find the longest contiguous substring of a string s that avoids certain "boring" substrings. In other words, given a string s and a small list of forbidden patterns b1, b2, ...

The problem gives us three arrays of equal length: - startTime[i] represents when the i-th job starts - endTime[i] represents when the i-th job finishes - profit[i] represents the money earned if we complete that job Our goal is to select a subset of jobs that do not overlap…

This problem asks us to determine which words from a given list can be constructed using the characters available in another string, chars. A word is considered good if every character it needs exists in chars in sufficient quantity.

In this problem, we are standing at a fixed position on a 2D plane, represented by location = [posx, posy]. Around us, there are multiple points, each with integer coordinates. We are allowed to rotate in place, but we cannot move.

The problem gives four points in a 2D coordinate system and asks whether those four points form a valid square. The points are not provided in any guaranteed order, which means we cannot assume adjacent points or diagonally opposite points are already grouped correctly.

The sequence starts with two fixed values:

The problem asks us to compute the maximum alternating subarray sum for a given integer array. A subarray is any contiguous sequence of elements from the array.

This problem asks us to find all words that are considered "uncommon" between two sentences. Each sentence is made up of lowercase words separated by single spaces. A word is considered uncommon if it satisfies two conditions: 1. It appears exactly once in one sentence. 2.

The problem asks us to compute the number of ways to completely tile a 2 x n board using two types of tiles: a domino (2 x 1) and a tromino shape.

The problem gives us a matrix called picture, where each cell contains either 'B' for a black pixel or 'W' for a white pixel. We are also given an integer target. We need to count how many black pixels qualify as "lonely pixels" under two strict conditions.

The problem asks us to calculate the total time each employee spends in the office per day based on a table of their in and out times.

The problem gives us an array named score, where each element represents the score earned by an athlete in a competition. Every athlete has a unique score, which means there are no ties to worry about when determining rankings.

The problem gives us n unique songs and asks us to build playlists of length goal. Songs may repeat, but two important constraints must always hold. First, every one of the n songs must appear at least once in the playlist.

This problem describes a two player game played on an array of stones. Each stone has a positive integer value, and the

In this problem, we are given an n x n board where each cell contains one of four possible values: - 'E', the ending position located at the top-left corner - 'S', the starting position located at the bottom-right corner - A digit character '1' through '9', representing points…

The problem gives us two integer arrays, nums1 and nums2. We must count the number of valid triplets that satisfy one of

The task is to normalize the case of a single word so that either all letters are lowercase or all are uppercase.

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.

We have an n × m grid. The king starts at the top-left cell (1,1) and must end there as well. Every other cell must be visited exactly once. Normal movement is allowed only between side-adjacent cells, but we may additionally install directed teleporters.

The problem asks us to find a missing value from an array that originally formed an arithmetic progression (AP). An arithmetic progression is a sequence where the difference between consecutive terms is constant, i.e., arr[i + 1] - arr[i] is the same for every consecutive pair.

The problem asks us to determine whether a sequence of integers represents a valid UTF-8 encoded byte stream. Each integer in the input array represents one byte, meaning only its lowest 8 bits matter.

The problem gives us a string s consisting only of uppercase English letters and an integer k. We are allowed to perform at most k replacement operations. In one operation, we can change any character in the string into any other uppercase English character.

This problem provides a database table named Users with two columns: userid and name. The userid column uniquely identifies each user, while the name column stores a person's name using a mixture of uppercase and lowercase English letters.

This problem asks us to verify whether a list of words is sorted according to a custom alphabet order, instead of the normal English alphabetical order. In normal lexicographical ordering, characters are compared from left to right using the standard alphabet.

We are given a row of n trees, each with a certain height, and our task is to adjust some of their heights so that the row forms a “beautiful” sequence.

We are given a connected undirected graph representing a road network. Every junction is a vertex, every road is an edge, and there is at most one edge between any pair of vertices.

This problem asks us to generate every possible subset of a given array of unique integers. A subset is any selection of elements from the array, including the empty subset and the subset containing every element.

In this problem, we are given a circular bus route with n stops numbered from 0 to n - 1. The array distance describes the distance between neighboring stops. Specifically, distance[i] represents the distance from stop i to stop (i + 1) % n.

Jack starts at position 0 on a number line. His jumps have fixed lengths: the first jump must have length 1, the second jump length 2, the third jump length 3, and so on. For every jump he may choose either direction.

We are given two strings. The first string is the newspaper headline, and the second string is the anonymous letter Vasya wants to build from it.

The problem gives us a collection of distinct points on a 2D plane. Each point is represented as [x, y], where x is the horizontal coordinate and y is the vertical coordinate.

We are given an undirected graph where vertices represent people and edges represent relationships. For every query (u, v), we must decide whether there exists a simple path from u to v whose length is odd. The keyword here is "simple". We are not allowed to revisit vertices.

This problem asks us to identify students who are "quiet" across all exams they participated in. A student is considered

We are asked to determine if a given positive integer can be represented as a triangular number. Triangular numbers are formed by arranging dots into an equilateral triangle, so the _n_-th triangular number is the sum of the first _n_ positive integers.

Tom uses his laptop during several disjoint time intervals. While he is actively using it, the laptop stays in normal mode and consumes P1 watts per minute. When he stops interacting with the laptop, the machine does not immediately switch to lower-power states.

The problem gives us a list of email addresses and asks how many unique destinations actually receive emails after applying Gmail-like normalization rules.

The problem asks us to sort a singly linked list using the insertion sort algorithm. Unlike array sorting problems where elements can be accessed directly by index, linked lists require sequential traversal, so insertion operations behave differently and require careful…

This problem asks us to identify all lucky numbers in a given matrix. A lucky number is defined as a value that satisfie

The problem gives us a binary array nums consisting of 0s and 1s and an integer k. The task is to transform the array so that all elements are 1s using the minimum number of operations called k-bit flips.

The problem gives us an array heights, where each value represents the height of a building. You start at building 0 and

Here is the complete, detailed technical solution guide for LeetCode 1044 - Longest Duplicate Substring, following your formatting rules exactly. The problem asks us to find the longest duplicated substring in a given string s.

The problem describes a car traveling from position 0 to a destination located target miles away. The car starts with startFuel liters of fuel, and every mile driven consumes exactly one liter of fuel.

This problem asks us to process a stream of non-negative integers and continuously maintain a compact representation of all numbers seen so far. Instead of storing every individual number separately, we want to group consecutive numbers into disjoint intervals.

The problem asks us to find the smallest element that appears in every row of a given m x n matrix mat, where each row is sorted in strictly increasing order. In other words, we need an element that is common to all rows and is the minimum among all such elements.

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 gives us a special type of array called a mountain array. A mountain array strictly increases until it reaches a single peak element, then strictly decreases afterward. For example: increases up to 5, then decreases.

The problem gives an array nums containing n distinct integers. Every number is supposed to come from the range [0, n], which means there are actually n + 1 possible values in total. Since the array only contains n numbers, exactly one value from that range is missing.

The problem gives us an array called boxes, where each integer represents the color of a box. We may repeatedly remove groups of adjacent boxes that share the same color. If we remove a group containing k boxes, we earn k k points.

The problem gives us k sorted integer lists, and we must find the smallest inclusive range [a, b] such that the range contains at least one element from every list. Each list is already sorted in non-decreasing order, which is a very important property.

In this problem, we are given the root node of a binary tree, and we need to compute the average value of all nodes at each depth level of the tree. A binary tree is organized into levels.

The problem describes a binary watch that uses LEDs to represent time. The watch has two sections. The top section contains 4 LEDs for the hour, and the bottom section contains 6 LEDs for the minutes. Each LED represents a binary digit.

The problem asks us to design an authentication system that manages tokens with expiration times. Each token is valid for a fixed timeToLive seconds starting from the moment it is generated or renewed.

The problem requires rearranging spaces in a given string text so that all words are separated by the maximum possible e

This problem asks us to design a leaderboard system that supports three operations efficiently. Each player has a unique playerId and an associated score. The leaderboard begins empty, and players can be added dynamically as operations are performed.

The problem asks us to group strings based on a special equivalence property. Specifically, two strings are special-equivalent if you can swap characters at even indices among themselves and characters at odd indices among themselves any number of times to make the two strings…

The problem asks us to sort a singly linked list in ascending order and return the head of the sorted list. The input is the head node of a linked list. Each node contains an integer value and a pointer to the next node.

The problem gives us an m x n binary matrix where each cell contains either 0 or 1. We must count how many rectangular submatrices consist entirely of ones. A submatrix is any contiguous rectangular region inside the matrix.

This problem asks us to find the maximum length of a contiguous subarray in a binary array where the number of 0s and 1s are equal. A contiguous subarray means the elements must appear consecutively in the original array. We are not allowed to rearrange elements or skip indices.

The task is to reverse a number given as a string, taking care of signs and leading zeros. The input can be a very large integer, up to 10,000 digits, possibly with leading zeros.

The problem asks us to count how many ways we can split a string into two non-empty parts such that both parts contain the same number of distinct characters. A split occurs between two adjacent characters.

We are given a text file written in INI format. Every meaningful line is either a section declaration such as [network] or a key-value assignment such as port=8080. Spaces around keys, values, and section brackets are irrelevant and must be removed in the final output.

The problem asks us to find the length of the shortest reference string that can encode a list of words. A reference string is formed by concatenating some of the words with a '' character at the end of each word.

The problem gives us a list of unique points on a 2D X-Y plane. Each point is represented as a pair of integers [x, y]. Our task is to choose any three distinct points and compute the area of the triangle formed by those points.

We have several jars of honey, and each jar starts with some amount of honey. Winnie repeatedly chooses the jar that currently contains the most honey. When Winnie picks a jar, two things may happen.

The problem asks us to maximize the number of employee transfer requests that can be fulfilled under the constraint that

This problem asks us to find a unique number in an array where every other number appears exactly three times. In simpler terms, if you imagine counting all the numbers in the array, every number except one will show up three times, and our task is to identify the number that…

The problem provides access to a single API, rand7(), which returns a uniformly random integer from 1 to 7. The task is to implement another function, rand10(), which must return a uniformly random integer from 1 to 10.

This problem gives us a database table named Tweets with two columns: | Column | Description | | --- | --- | | tweetid |

The problem asks us to convert a positive integer into the column naming format used by Microsoft Excel. Excel labels columns alphabetically instead of numerically. The sequence begins as: The input, columnNumber, represents a 1-based column index.

The problem asks us to count all the negative numbers in a 2D matrix grid where each row and column is sorted in non-inc

We are given a simple polygon listed in clockwise order. The first two vertices form a horizontal edge AB, and every other vertex lies strictly on the same side of that edge. Along the segment AB, every integer-coordinate point is a possible location for a watchtower.

We are asked to count how many distinct substrings of a given string t start with a string sbegin and end with another string send. The key detail is that substrings are considered different only by their content, not by their position in t.

This problem asks us to merge user accounts based on shared email addresses. Each account is represented as a list of strings. The first string is the user's name, and every remaining string is an email address associated with that account.

The problem gives us an integer array nums whose length is exactly 2 n. Among all the numbers in the array, there are n + 1 distinct values. One special value appears exactly n times, while every other value appears only once.

This problem asks us to find all shortest transformation sequences from beginWord to endWord, where each transformation changes exactly one character and every intermediate word must exist in wordList. We can think of the problem as navigating through a graph.

We have an n × m chessboard. A billiard ball moves diagonally like a bishop, but unlike a bishop it reflects off the borders of the board. When it hits a vertical wall, the horizontal component of the direction flips. When it hits a horizontal wall, the vertical component flips.

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

This problem asks us to add two polynomials represented as singly linked lists. Each node in the linked list represents a single term of a polynomial, with a coefficient and a power.

This problem asks us to locate the first occurrence of one string inside another string. The string we are searching for is called needle, and the larger string we search inside is called haystack.

It looks like you want the full detailed solution guide, but the specific LeetCode problem number and statement are missing from your latest request template. You included the formatting instructions and structure, but not which problem to solve beyond prior context.

The problem asks us to construct a permutation of the integers from 1 to n such that the array satisfies a special condition.

We are given an array of positive integers and many interval queries. For each query [l, r], we look only at the subarray between those indices and compute a value called its power. If a number x appears k times inside the subarray, then x contributes k² x to the answer.

This problem is asking us to calculate the probability that, when tossing a set of coins, exactly a specific number of them come up heads. Each coin has its own individual probability of landing heads, which is given in the input array prob.

The problem gives us a list of rectangles, where each rectangle is represented as [li, wi]. Here, li is the rectangle's length and wi is its width. From each rectangle, we want to determine the largest square that can be cut from it.

The problem gives us a rooted tree with n nodes labeled from 0 to n - 1. Instead of providing the tree as adjacency lists or edges, the input is represented using a parent array. For every node i, parent[i] tells us which node is its direct parent.

We are given six words and must arrange them into a very specific crossword shape. The shape looks like a rectangular infinity symbol. There are three horizontal words and three vertical words, and they intersect at fixed positions.

The problem asks us to find the length of the longest substring that appears at least twice in a given string s. A substring is a contiguous sequence of characters inside a string. The repeated substrings may overlap with each other, which is an important detail.

The problem gives us a single integer, area, which represents the area of a rectangle. Our task is to find two integers: - L, the length - W, the width such that: 1. L W == area 2. L = W 3.

We have a tree where each vertex initially contains some number of beavers. The robot starts at a fixed vertex s. Every time it traverses an edge from u to v, it immediately eats exactly one beaver at v. If v already has zero beavers left, the move is impossible.

The problem asks us to find the lexicographically largest contiguous subarray of length k from a given array of distinct integers. Two arrays are compared lexicographically.

This problem asks us to generate all possible combinations of size k from the numbers in the inclusive range [1, n].

This problem asks us to count the number of arrays of length n where each element is between 1 and m inclusive, and the

The problem gives us two traversal orders of the same binary tree: - preorder, which visits nodes in the order: root → left subtree → right subtree - postorder, which visits nodes in the order: left subtree → right subtree → root Our task is to reconstruct and return the…

The problem requires constructing a binary expression tree from a postfix arithmetic expression and implementing a metho

The problem gives us a two dimensional matrix of integers with m rows and n columns. We must modify the matrix in place so that whenever a cell contains 0, every element in that cell's entire row and entire column also becomes 0.

The problem gives us an array of phrases, where each phrase is a string made of lowercase English letters and spaces. Every phrase is well-formed, meaning there are no leading or trailing spaces and no consecutive spaces.