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LeetCode problem #1774

LeetCode problem #1300

Find maximum value that can be obtained with given weight capacity

Add two numbers represented as linked lists where digits are stored in reverse order

Given a sorted dictionary of alien language, find the order of characters in the alien alphabet

Find all possible paths from source node to target node in a directed acyclic graph (DAG)

Find all articulation points in an undirected graph - vertices whose removal increases the number of connected components

Find shortest paths from a source vertex to all other vertices in a weighted graph, capable of handling negative edge weights

Find shortest path between two vertices in an unweighted graph using BFS traversal

Traverse a binary tree in inorder (left -> root -> right)

Traverse a binary tree in preorder (root -> left -> right)

Traverse the boundary of a binary tree in anti-clockwise direction.

Implement breadth-first search traversal of a graph

Find the maximum profit from buying and selling stock with at most one transaction

Find the celebrity in a party of n people using the minimum number of questions.

Determine if an array is sorted in ascending, descending, or not sorted at all

Determine if a string reads the same forwards and backwards, ignoring case and non-alphanumeric characters.

Determine if one string is a rotation of another string by checking if it can be formed by rotating the characters.

Detect if a linked list has a cycle and find the starting point of the cycle

Count the number of distinct ways to reach the top of n stairs

Create a deep copy of an undirected graph represented with adjacency lists

Find the minimum number of coins needed to make a given amount

Count the number of ways to make a given amount using coins

Connect ropes with minimum cost using greedy approach with heap

Construct a binary tree from preorder and inorder traversal sequences.

Convert a sorted array to a height-balanced binary search tree.

Create a deep copy of a linked list where each node has a random pointer

Generate the nth term of the count-and-say sequence.

Count the number of nodes in a binary tree where the path from root to that node has no nodes with values greater than the current node.

Determine if you can finish all courses given prerequisite relationships using topological sorting

Find the number of days until a warmer temperature for each day.

Decode a string encoded with the format k[encoded_string].

Delete a node from a linked list when you only have access to that node

Implement depth-first search traversal for graphs

Design a circular queue with fixed size that supports enqueue, dequeue, front, rear, isEmpty, and isFull operations.

Determine if a directed graph contains a cycle

Detect if a linked list has a cycle using Floyd's cycle detection algorithm

Determine if an undirected graph contains a cycle

Find the diameter (longest path) of a binary tree.

Find minimum operations to convert one string to another

Find the minimum number of operations (insert, delete, replace) required to transform one string into another.

Evaluate the value of an arithmetic expression in Reverse Polish Notation.

Retry strategy that progressively increases delay between retry attempts to handle transient failures and prevent system overload

Evaluate mathematical expressions with proper operator precedence and parentheses.

Calculate the nth Fibonacci number using dynamic programming

Find all bridges (critical edges) in an undirected graph using Tarjan's algorithm

Find the duplicate number in an array containing n+1 integers where each integer is between 1 and n (inclusive)

Find the k largest elements from an unsorted array

Find the k smallest elements from an unsorted array

Find the majority element that appears more than n/2 times using Boyer-Moore majority vote algorithm

Design data structure to find median from continuous stream of integers

Find the middle node of a linked list using the two-pointer technique

Find the missing number in an array containing n distinct numbers taken from 1, 2, 3, ..., n+1

Find and return the largest element in an array of integers

Find and return the second largest element in an array of integers

Find the first non-repeating character in a string and return its index.

Flatten a binary tree into a linked list in-place using preorder traversal.

Flatten a multilevel doubly linked list into a single level

Find shortest paths between all pairs of vertices in a weighted graph using dynamic programming

Find furthest building reachable using optimal allocation of bricks and ladders

Generate all possible permutations of a given string.

Group strings that are anagrams of each other together.

Scaling strategy that increases system capacity by adding more machines or instances rather than upgrading existing hardware

Find maximum amount that can be robbed without robbing adjacent houses

Implement a queue using arrays or linked lists with O(1) time complexity for all operations.

Implement a queue using two stacks with O(1) amortized time complexity for all operations.

Design and implement a stack data structure with push, pop, top, and empty operations

Implement a stack using two queues with O(1) amortized time complexity for all operations.

Find the first occurrence of a substring in a string, similar to strstr() function.

Find the intersection of two arrays and return the result as an array.

Find the intersection node of two linked lists

Invert (mirror) a binary tree by swapping left and right children

Full-text search and information retrieval using inverted indexes

Check if a graph can be colored with exactly two colors such that no two adjacent nodes have the same color

Find the kth largest element in an unsorted array

Find kth smallest element in row and column sorted matrix using heap

Find the largest rectangle that can be formed in a histogram

Traverse a binary tree level by level from left to right.

Find the longest common prefix string amongst an array of strings.

Find the length of the longest common subsequence between two strings

Find the length of the longest consecutive elements sequence in an unsorted array.

Find the length of the longest increasing subsequence in an array

Find the longest palindromic substring in a given string

Find the longest substring that appears at least twice in a string

Find the length of the longest substring without repeating characters

Find the lowest common ancestor of two nodes in a binary tree.

Design a stack that supports push, pop, top, peekMax, and popMax operations

Maximize array sum by flipping signs of k elements using greedy heap approach

Find the maximum depth (height) of a binary tree

Find the maximum path sum in a binary tree.

Find the contiguous subarray with maximum sum using Kadane's algorithm

Find minimum number of meeting rooms required using heap

Merge k sorted arrays into one sorted array using heap

Merge k sorted linked lists into one sorted linked list

Merge two sorted arrays into a single sorted array in-place

Merge two sorted linked lists into one sorted linked list

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time

Find minimum insertions needed to balance parentheses string

Find minimum refueling stops to reach target using greedy max-heap approach

Find the minimum spanning tree of a weighted undirected graph using Kruskal's and Prim's algorithms

Find the minimum number of swaps required to sort an array.

Find the minimum window substring that contains all characters of another string

Find the missing number in an array containing n distinct numbers taken from 0, 1, 2, ..., n.

Move all zeros in an array to the end while maintaining the relative order of non-zero elements

Find the time it takes for a signal to reach all nodes in a network using shortest path algorithms

Find the next greater element for each element in an array.

Count the number of islands in a 2D grid

Concurrency control mechanism that assumes conflicts are rare and handles them when they occur, using version numbers or timestamps to detect concurrent modifications

Check if a linked list is a palindrome using O(1) extra space

Partition a linked list around a value x such that all nodes less than x come before nodes greater than or equal to x

Check if there exists a root-to-leaf path with given sum.

Traverse binary tree in postorder (left, right, root)

Check if a given integer is a power of two.

Print all root-to-leaf paths in a binary tree

Return an array where each element is the product of all elements except the element at that index.

Find minimum removals to reduce array size by half using greedy heap approach

Implement regular expression matching with '.' and '*'

Implement regular expression matching with support for '.' and '*'

Remove all duplicate values from a sorted linked list

Remove k digits from a number to make it as small as possible

Remove the nth node from the end of a linked list in one pass

Reorder a linked list by interleaving nodes from the beginning and end

Reorganize string so no two adjacent characters are the same

Reverse a singly linked list in-place

Reverse the order of elements in an array in-place and return the modified array

Reverse the bits of a given 32-bit unsigned integer.

Reverse every k consecutive nodes in a linked list

Reverse a string in-place using O(1) extra memory.

Rotate an array to the right by k steps where k is non-negative

Rotate a linked list to the right by k places

Find the minimum time for all oranges to rot using BFS

Serialize a binary tree to a string and deserialize it back to the original tree

Find the single number that appears once in an array where every other number appears twice.

Find the maximum element in each sliding window of size k

Find the maximum element in each sliding window of size k.

Find median in each sliding window using two heaps

Find the smallest substring that contains all characters of a given pattern

Sort characters in string by frequency using heap or bucket sort

Sort a linked list in O(n log n) time using constant extra space

Calculate the span of stock prices for each day

Compress a string by replacing consecutive characters with character and count.

Find all strongly connected components in a directed graph

Find a subarray with a given sum in an array of positive integers.

Swap every two adjacent nodes in a linked list

Check if a binary tree is symmetric around its center.

Schedule tasks with cooling period using greedy approach with heap

Find all unique triplets in the array which gives the sum of zero

Find the k most frequent elements in an array

Find a linear ordering of vertices in a directed acyclic graph

Calculate how much rainwater can be trapped between bars of different heights

Find two numbers in an array that add up to a target value.

Find the nth ugly number using heap-based approach

Count unique paths from top-left to bottom-right in a grid

Determine if two strings are anagrams of each other

Determine if the input string has valid brackets that are properly opened and closed

Check if a string containing only parentheses is valid.

Traverse a binary tree vertically and return nodes by columns

Determine if a string can be segmented into space-separated words from a dictionary.

Return all possible ways to break a string into dictionary words

Find the shortest transformation sequence from beginWord to endWord using single character changes

Traverse a binary tree level by level in zigzag order