Medium LeetCode Problems: Page 5 of 8

Problems 801 to 1,000 of the 1,579 Medium-rated problems in this library, continuing the list on the Medium hub.

Page 5 of 8

Medium problems, page 5
No.	Problem	Topics
1915	Number of Wonderful Substrings	Bit Manipulation, Hash Table, String +1
1921	Eliminate Maximum Number of Monsters	Greedy, Array, Sorting
1922	Count Good Numbers	Recursion, Math
1926	Nearest Exit from Entrance in Maze	Breadth-First Search, Array, Matrix
1927	Sum Game	Greedy, Math, String +1
1930	Unique Length-3 Palindromic Subsequences	Bit Manipulation, Hash Table, String +1
1936	Add Minimum Number of Rungs	Greedy, Array
1937	Maximum Number of Points with Cost	Array, Dynamic Programming, Matrix
1942	The Number of the Smallest Unoccupied Chair	Array, Hash Table, Heap (Priority Queue)
1943	Describe the Painting	Array, Hash Table, Prefix Sum +1
1946	Largest Number After Mutating Substring	Greedy, Array, String
1947	Maximum Compatibility Score Sum	Bit Manipulation, Array, Dynamic Programming +2
1953	Maximum Number of Weeks for Which You Can Work	Greedy, Array
1954	Minimum Garden Perimeter to Collect Enough Apples	Math, Binary Search
1958	Check if Move is Legal	Array, Enumeration, Matrix
1959	Minimum Total Space Wasted With K Resizing Operations	Array, Dynamic Programming
1962	Remove Stones to Minimize the Total	Greedy, Array, Heap (Priority Queue)
1963	Minimum Number of Swaps to Make the String Balanced	Stack, Greedy, Two Pointers +1
1968	Array With Elements Not Equal to Average of Neighbors	Greedy, Array, Sorting
1969	Minimum Non-Zero Product of the Array Elements	Greedy, Recursion, Math
1975	Maximum Matrix Sum	Greedy, Array, Matrix
1976	Number of Ways to Arrive at Destination	Graph, Topological Sort, Dynamic Programming +1
1980	Find Unique Binary String	Array, Hash Table, String +1
1981	Minimize the Difference Between Target and Chosen Elements	Array, Dynamic Programming, Matrix
1985	Find the Kth Largest Integer in the Array	Array, String, Divide and Conquer +3
1986	Minimum Number of Work Sessions to Finish the Tasks	Bit Manipulation, Array, Dynamic Programming +2
1992	Find All Groups of Farmland	Depth-First Search, Breadth-First Search, Array +1
1993	Operations on Tree	Tree, Depth-First Search, Breadth-First Search +3
1996	The Number of Weak Characters in the Game	Stack, Greedy, Array +2
1997	First Day Where You Have Been in All the Rooms	Array, Dynamic Programming
2001	Number of Pairs of Interchangeable Rectangles	Array, Hash Table, Math +2
2002	Maximum Product of the Length of Two Palindromic Subsequences	Bit Manipulation, String, Dynamic Programming +2
2007	Find Original Array From Doubled Array	Greedy, Array, Hash Table +1
2008	Maximum Earnings From Taxi	Array, Hash Table, Binary Search +2
2012	Sum of Beauty in the Array	Array
2013	Detect Squares	Design, Array, Hash Table +1
2017	Grid Game	Array, Matrix, Prefix Sum
2018	Check if Word Can Be Placed In Crossword	Array, Enumeration, Matrix
2023	Number of Pairs of Strings With Concatenation Equal to Target	Array, Hash Table, String +1
2024	Maximize the Confusion of an Exam	String, Binary Search, Prefix Sum +1
2028	Find Missing Observations	Array, Math, Simulation
2029	Stone Game IX	Greedy, Array, Math +2
2033	Minimum Operations to Make a Uni-Value Grid	Array, Math, Matrix +1
2034	Stock Price Fluctuation	Design, Hash Table, Data Stream +2
2038	Remove Colored Pieces if Both Neighbors are the Same Color	Greedy, Math, String +1
2039	The Time When the Network Becomes Idle	Breadth-First Search, Graph, Array
2043	Simple Bank System	Design, Array, Hash Table +1
2044	Count Number of Maximum Bitwise-OR Subsets	Bit Manipulation, Array, Backtracking +1
2048	Next Greater Numerically Balanced Number	Hash Table, Math, Backtracking +2
2049	Count Nodes With the Highest Score	Tree, Depth-First Search, Array +1
2054	Two Best Non-Overlapping Events	Array, Binary Search, Dynamic Programming +2
2055	Plates Between Candles	Array, String, Binary Search +1
2058	Find the Minimum and Maximum Number of Nodes Between Critical Points	Linked List
2059	Minimum Operations to Convert Number	Breadth-First Search, Array
2063	Vowels of All Substrings	Math, String, Dynamic Programming +1
2064	Minimized Maximum of Products Distributed to Any Store	Greedy, Array, Binary Search
2070	Most Beautiful Item for Each Query	Array, Binary Search, Sorting
2074	Reverse Nodes in Even Length Groups	Linked List
2075	Decode the Slanted Ciphertext	String, Simulation
2079	Watering Plants	Array, Simulation
2080	Range Frequency Queries	Design, Segment Tree, Array +2
2086	Minimum Number of Food Buckets to Feed the Hamsters	Greedy, String, Dynamic Programming
2087	Minimum Cost Homecoming of a Robot in a Grid	Greedy, Array
2090	K Radius Subarray Averages	Array, Sliding Window
2091	Removing Minimum and Maximum From Array	Greedy, Array
2095	Delete the Middle Node of a Linked List	Linked List, Two Pointers
2096	Step-By-Step Directions From a Binary Tree Node to Another	Tree, Depth-First Search, String +1
2100	Find Good Days to Rob the Bank	Array, Dynamic Programming, Prefix Sum
2101	Detonate the Maximum Bombs	Depth-First Search, Breadth-First Search, Graph +3
2104	Sum of Subarray Ranges	Stack, Array, Monotonic Stack
2105	Watering Plants II	Array, Two Pointers, Simulation
2109	Adding Spaces to a String	Array, Two Pointers, String +1
2110	Number of Smooth Descent Periods of a Stock	Array, Math, Two Pointers +2
2115	Find All Possible Recipes from Given Supplies	Graph, Topological Sort, Array +2
2116	Check if a Parentheses String Can Be Valid	Stack, Greedy, String
2120	Execution of All Suffix Instructions Staying in a Grid	String, Simulation
2121	Intervals Between Identical Elements	Array, Hash Table, Prefix Sum
2125	Number of Laser Beams in a Bank	Array, Math, String +1
2126	Destroying Asteroids	Greedy, Array, Sorting
2130	Maximum Twin Sum of a Linked List	Stack, Linked List, Two Pointers
2131	Longest Palindrome by Concatenating Two Letter Words	Greedy, Array, Hash Table +2
2134	Minimum Swaps to Group All 1's Together II	Array, Sliding Window
2135	Count Words Obtained After Adding a Letter	Bit Manipulation, Array, Hash Table +2
2139	Minimum Moves to Reach Target Score	Greedy, Math
2140	Solving Questions With Brainpower	Array, Dynamic Programming
2145	Count the Hidden Sequences	Array, Prefix Sum
2146	K Highest Ranked Items Within a Price Range	Breadth-First Search, Array, Matrix +2
2149	Rearrange Array Elements by Sign	Array, Two Pointers, Simulation
2150	Find All Lonely Numbers in the Array	Array, Hash Table, Counting
2155	All Divisions With the Highest Score of a Binary Array	Array
2161	Partition Array According to Given Pivot	Array, Two Pointers, Simulation
2162	Minimum Cost to Set Cooking Time	Math, Enumeration
2165	Smallest Value of the Rearranged Number	Math, Sorting
2166	Design Bitset	Design, Array, Hash Table +1
2170	Minimum Operations to Make the Array Alternating	Greedy, Array, Hash Table +1
2171	Removing Minimum Number of Magic Beans	Greedy, Array, Enumeration +2
2177	Find Three Consecutive Integers That Sum to a Given Number	Math, Simulation
2178	Maximum Split of Positive Even Integers	Greedy, Math, Backtracking
2181	Merge Nodes in Between Zeros	Linked List, Simulation
2182	Construct String With Repeat Limit	Greedy, Hash Table, String +2
2186	Minimum Number of Steps to Make Two Strings Anagram II	Hash Table, String, Counting
2187	Minimum Time to Complete Trips	Array, Binary Search
2191	Sort the Jumbled Numbers	Array, Sorting
2192	All Ancestors of a Node in a Directed Acyclic Graph	Depth-First Search, Breadth-First Search, Graph +1
2195	Append K Integers With Minimal Sum	Greedy, Array, Math +1
2196	Create Binary Tree From Descriptions	Tree, Array, Hash Table +1
2201	Count Artifacts That Can Be Extracted	Array, Hash Table, Simulation
2202	Maximize the Topmost Element After K Moves	Greedy, Array
2207	Maximize Number of Subsequences in a String	Greedy, String, Prefix Sum
2208	Minimum Operations to Halve Array Sum	Greedy, Array, Heap (Priority Queue)
2211	Count Collisions on a Road	Stack, String, Simulation
2212	Maximum Points in an Archery Competition	Bit Manipulation, Array, Backtracking +1
2216	Minimum Deletions to Make Array Beautiful	Stack, Greedy, Array
2217	Find Palindrome With Fixed Length	Array, Math
2221	Find Triangular Sum of an Array	Array, Math, Combinatorics +1
2222	Number of Ways to Select Buildings	String, Dynamic Programming, Prefix Sum
2225	Find Players With Zero or One Losses	Array, Hash Table, Counting +1
2226	Maximum Candies Allocated to K Children	Array, Binary Search
2232	Minimize Result by Adding Parentheses to Expression	String, Enumeration
2233	Maximum Product After K Increments	Greedy, Array, Heap (Priority Queue)
2240	Number of Ways to Buy Pens and Pencils	Math, Enumeration
2241	Design an ATM Machine	Greedy, Design, Array
2244	Minimum Rounds to Complete All Tasks	Greedy, Array, Hash Table +1
2245	Maximum Trailing Zeros in a Cornered Path	Array, Matrix, Prefix Sum
2249	Count Lattice Points Inside a Circle	Geometry, Array, Hash Table +2
2250	Count Number of Rectangles Containing Each Point	Binary Indexed Tree, Array, Hash Table +2
2256	Minimum Average Difference	Array, Prefix Sum
2257	Count Unguarded Cells in the Grid	Array, Matrix, Simulation
2260	Minimum Consecutive Cards to Pick Up	Array, Hash Table, Sliding Window
2261	K Divisible Elements Subarrays	Trie, Array, Hash Table +3
2265	Count Nodes Equal to Average of Subtree	Tree, Depth-First Search, Binary Tree
2266	Count Number of Texts	Hash Table, Math, String +1
2270	Number of Ways to Split Array	Array, Prefix Sum
2271	Maximum White Tiles Covered by a Carpet	Greedy, Array, Binary Search +3
2274	Maximum Consecutive Floors Without Special Floors	Array, Sorting
2275	Largest Combination With Bitwise AND Greater Than Zero	Bit Manipulation, Array, Hash Table +1
2279	Maximum Bags With Full Capacity of Rocks	Greedy, Array, Sorting
2280	Minimum Lines to Represent a Line Chart	Geometry, Array, Math +2
2284	Sender With Largest Word Count	Array, Hash Table, String +1
2285	Maximum Total Importance of Roads	Greedy, Graph, Sorting +1
2288	Apply Discount to Prices	String
2289	Steps to Make Array Non-decreasing	Stack, Array, Linked List +1
2294	Partition Array Such That Maximum Difference Is K	Greedy, Array, Sorting
2295	Replace Elements in an Array	Array, Hash Table, Simulation
2300	Successful Pairs of Spells and Potions	Array, Two Pointers, Binary Search +1
2304	Minimum Path Cost in a Grid	Array, Dynamic Programming, Matrix
2305	Fair Distribution of Cookies	Bit Manipulation, Array, Dynamic Programming +2
2310	Sum of Numbers With Units Digit K	Greedy, Math, Dynamic Programming +1
2311	Longest Binary Subsequence Less Than or Equal to K	Greedy, Memoization, String +1
2316	Count Unreachable Pairs of Nodes in an Undirected Graph	Depth-First Search, Breadth-First Search, Union Find +1
2317	Maximum XOR After Operations	Bit Manipulation, Array, Math
2320	Count Number of Ways to Place Houses	Dynamic Programming
2326	Spiral Matrix IV	Array, Linked List, Matrix +1
2327	Number of People Aware of a Secret	Queue, Dynamic Programming, Simulation
2332	The Latest Time to Catch a Bus	Array, Two Pointers, Binary Search +1
2333	Minimum Sum of Squared Difference	Greedy, Array, Binary Search +2
2336	Smallest Number in Infinite Set	Design, Hash Table, Ordered Set +1
2337	Move Pieces to Obtain a String	Two Pointers, String
2342	Max Sum of a Pair With Equal Sum of Digits	Array, Hash Table, Sorting +1
2343	Query Kth Smallest Trimmed Number	Array, String, Divide and Conquer +4
2348	Number of Zero-Filled Subarrays	Array, Math
2349	Design a Number Container System	Design, Hash Table, Ordered Set +1
2352	Equal Row and Column Pairs	Array, Hash Table, Matrix +1
2353	Design a Food Rating System	Design, Array, Hash Table +3
2358	Maximum Number of Groups Entering a Competition	Greedy, Array, Math +1
2359	Find Closest Node to Given Two Nodes	Depth-First Search, Graph
2364	Count Number of Bad Pairs	Array, Hash Table, Math +1
2365	Task Scheduler II	Array, Hash Table, Simulation
2368	Reachable Nodes With Restrictions	Tree, Depth-First Search, Breadth-First Search +4
2369	Check if There is a Valid Partition For The Array	Array, Dynamic Programming
2370	Longest Ideal Subsequence	Hash Table, String, Dynamic Programming
2374	Node With Highest Edge Score	Graph, Hash Table
2375	Construct Smallest Number From DI String	Stack, Greedy, String +1
2380	Time Needed to Rearrange a Binary String	String, Dynamic Programming, Simulation
2381	Shifting Letters II	Array, String, Prefix Sum
2384	Largest Palindromic Number	Greedy, Hash Table, String +1
2385	Amount of Time for Binary Tree to Be Infected	Tree, Depth-First Search, Breadth-First Search +2
2390	Removing Stars From a String	Stack, String, Simulation
2391	Minimum Amount of Time to Collect Garbage	Array, String, Prefix Sum
2396	Strictly Palindromic Number	Brainteaser, Math, Two Pointers
2397	Maximum Rows Covered by Columns	Bit Manipulation, Array, Backtracking +2
2400	Number of Ways to Reach a Position After Exactly k Steps	Math, Dynamic Programming, Combinatorics
2401	Longest Nice Subarray	Bit Manipulation, Array, Sliding Window
2405	Optimal Partition of String	Greedy, Hash Table, String
2406	Divide Intervals Into Minimum Number of Groups	Greedy, Array, Two Pointers +3
2410	Maximum Matching of Players With Trainers	Greedy, Array, Two Pointers +1
2411	Smallest Subarrays With Maximum Bitwise OR	Bit Manipulation, Array, Binary Search +1
2414	Length of the Longest Alphabetical Continuous Substring	String
2415	Reverse Odd Levels of Binary Tree	Tree, Depth-First Search, Breadth-First Search +1
2419	Longest Subarray With Maximum Bitwise AND	Bit Manipulation, Brainteaser, Array
2420	Find All Good Indices	Array, Dynamic Programming, Prefix Sum
2424	Longest Uploaded Prefix	Union Find, Design, Binary Indexed Tree +5
2425	Bitwise XOR of All Pairings	Bit Manipulation, Brainteaser, Array
2428	Maximum Sum of an Hourglass	Array, Matrix, Prefix Sum
2429	Minimize XOR	Greedy, Bit Manipulation
2433	Find The Original Array of Prefix Xor	Bit Manipulation, Array
2434	Using a Robot to Print the Lexicographically Smallest String	Stack, Greedy, Hash Table +1
2438	Range Product Queries of Powers	Bit Manipulation, Array, Prefix Sum
2439	Minimize Maximum of Array	Greedy, Array, Binary Search +2
2442	Count Number of Distinct Integers After Reverse Operations	Array, Hash Table, Math +1

Problems with a complete Python solution are listed first, then by ascending problem number. Or go by technique instead: all LeetCode patterns.