heap priority queue

Merge k Sorted Lists

Merge k Sorted Lists requires efficiently combining multiple sorted linked lists into one using pointers and priority qu…

Kth Largest Element in an Array

Find the kth largest element in an unsorted array using optimal approaches like Quickselect or heaps.

The Skyline Problem

The Skyline Problem requires calculating a city's silhouette using array manipulation and divide-and-conquer techniques …

Sliding Window Maximum

Solve the "Sliding Window Maximum" problem using efficient techniques like the sliding window, deque, and priority queue…

Ugly Number II

Find the nth ugly number, where ugly numbers have prime factors limited to 2, 3, and 5.

Find Median from Data Stream

Implement a MedianFinder class that supports adding numbers and finding the median from a data stream.

Top K Frequent Elements

Find the k most frequent elements from an array using efficient algorithms like hashing and sorting.

Design Twitter

Design Twitter requires implementing post, follow, unfollow, and news feed retrieval using linked-list pointer manipulat…

Find K Pairs with Smallest Sums

Find K Pairs with Smallest Sums combines arrays and heap usage to select the smallest sum pairs efficiently.

Kth Smallest Element in a Sorted Matrix

Find the kth smallest element in a sorted n x n matrix using efficient binary search or heap strategies for optimized me…

Trapping Rain Water II

Solve Trapping Rain Water II using breadth-first search and priority queues for efficient water trapping in a matrix.

Strong Password Checker

The Strong Password Checker problem challenges you to optimize password strength while minimizing steps using greedy alg…

Sort Characters By Frequency

Sort Characters By Frequency requires counting characters efficiently and rearranging a string in descending frequency o…

Sliding Window Median

Compute the median for each sliding window of size k in an array using efficient array scanning and hash lookup techniqu…

IPO

Maximize total capital by selecting up to k projects, based on initial capital and project profits using a greedy strate…

Relative Ranks

Solve Relative Ranks by sorting scores with original indices, then writing medal labels or numeric places back in answer…

Task Scheduler

Task Scheduler is solved by counting task frequencies and computing how cooldown gaps force idle slots around the most f…

Course Schedule III

Solve the 'Course Schedule III' problem with a greedy approach involving course selection and validation of constraints.

Smallest Range Covering Elements from K Lists

Find the minimal range covering at least one number from each of k sorted lists using array scanning and hash lookup eff…

Find K Closest Elements

Identify the k integers closest to a target x in a sorted array using binary search and two-pointer strategies efficient…

Split Array into Consecutive Subsequences

Verify if it's possible to split a sorted array into consecutive subsequences of length 3 or more.

Cut Off Trees for Golf Event

Determine the minimum steps to cut all trees in a forest matrix in ascending height order using BFS traversal and priori…

Top K Frequent Words

Solve Top K Frequent Words by counting each word, then ordering ties alphabetically so frequency wins before lexicograph…

Kth Largest Element in a Stream

Find the kth largest element in a dynamic stream using binary-tree traversal and efficient state tracking with a min-hea…