Review: Hard Problems

See all hard problems: #hard

- LintCode: Surplus Value Backpack
- Lintcode: String Replace
- LintCode: Sliding Puzzle III
- LintCode: Minimum Difference
- LintCode: Minimum Cycle Section
- LintCode: K Spaced Array Sorting
- LintCode: Calculate Maximum Value II
- LeetCode: Word Search II
- Leetcode: Word Search
- Leetcode: Word Ladder II
- Leetcode: Word Frequency
- Leetcode: Valid Tic-Tac-Toe State
- Leetcode: Unique Letter String
- Leetcode: Unique Binary Search Trees II
- Leetcode: Unique Binary Search Trees
- Leetcode: Trips and Users
- Leetcode: Trapping Rain Water II
- LeetCode: Trapping Rain Water
- Leetcode: Transpose File
- Leetcode: Transform to Chessboard
- Leetcode: The Skyline Problem
- LeetCode: Text Justification
- Leetcode: Tallest Billboard
- Leetcode: Sum of Two Integers
- Leetcode: Sum of Subsequence Widths
- Leetcode: Sum of Distances in Tree
- Leetcode: Sudoku Solver
- Leetcode: Substring with Concatenation of All Words
- Leetcode: Students Report By Geography
- Leetcode: Student Attendance Record II
- Leetcode: Split Array With Same Average
- Leetcode: Special Binary String
- LeetCode: Soup Servings
- Leetcode: Smallest Rotation with Highest Score
- LeetCode: Sliding Window Median
- LeetCode: Sliding Window Maximum
- LeetCode: Shortest Palindrome
- Leetcode: Search for a Range
- Leetcode: Reverse Subarray To Maximize Array Value
- Leetcode: Reverse Nodes in k-Group
- Leetcode: Repeated Substring Pattern
- Leetcode: Remove Invalid Parentheses
- Leetcode: Remove Duplicates from Sorted List II
- Leetcode: Remove Duplicate Letters
- Leetcode: Remove Boxes
- Leetcode: Remove 9
- Leetcode: Random Pick with Blacklist
- Leetcode: Race Car
- Leetcode: Preimage Size of Factorial Zeroes Function
- Leetcode: Prefix and Suffix Search
- Leetcode: Populating Next Right Pointers in Each Node II
- Leetcode: Poor Pigs
- Leetcode: Palindrome Partitioning II
- LeetCode: Paint House II
- Leetcode: Number of Squareful Arrays
- Leetcode: Number of Distinct Islands II
- Leetcode: Number of Atoms
- Leetcode: Nth Digit
- Leetcode: N-Queens
- LeetCode: My Calendar III
- Leetcode: Minimum Window Substring
- LeetCode: Minimum Unique Word Abbreviation
- Leetcode: Minimum Cost Tree From Leaf Values
- LeetCode: Median Employee Salary
- LeetCode: Maximum Students Taking Exam
- LeetCode: Maximum Product Subarray
- Leetcode: Maximum Product of Three Numbers
- Leetcode: Maximum Gap
- LeetCode: Maximal Rectangle
- Leetcode: Max Points on a Line
- Leetcode: Max Chunks To Make Sorted II
- Leetcode: Making A Large Island
- LeetCode: Make Array Strictly Increasing
- Leetcode: Majority Element II
- Leetcode: Majority Element
- Leetcode: LRU Cache
- Leetcode: Longest Substring with At Most Two Distinct Characters
- Leetcode: Longest Substring with At Most K Distinct Characters
- Leetcode: Longest Consecutive Sequence
- Leetcode: Last Substring in Lexicographical Order
- Leetcode: Largest Rectangle in Histogram
- LeetCode: Jump Game II
- Leetcode: Integer to English Words
- Leetcode: Insert Delete GetRandom O(1) – Duplicates allowed
- Leetcode: Human Traffic of Stadium
- LeetCode: House Robber III
- LeetCode: House Robber II
- Leetcode: Happy Number
- Leetcode: Gas Station
- LeetCode: Frog Jump
- LeetCode: Flatten Nested List Iterator
- Leetcode: First Missing Positive
- LeetCode: Find the Closest Palindrome
- LeetCode: Find Median Given Frequency of Numbers
- Leetcode: Find Eventual Safe States
- Leetcode: Find Cumulative Salary of an Employee
- Leetcode: Employee Free Time
- Leetcode: Edit Distance
- Leetcode: Dungeon Game
- Leetcode: Distinct Subsequences II

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