Hash Table Problems
611 Hash Table LeetCode problems · Solve with AI-powered hints & step-by-step explanations.
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1 Two Sum Easy3 Longest Substring Without Repeating Characters Medium13 Roman to Integer Easy49 Group Anagrams Medium73 Set Matrix Zeroes Medium76 Minimum Window Substring Hard105 Construct Binary Tree from Preorder and Inorder Traversal Medium128 Longest Consecutive Sequence Medium133 Clone Graph Medium139 Word Break Medium141 Linked List Cycle Easy146 LRU Cache Medium169 Majority Element Easy208 Implement Trie (Prefix Tree) Medium217 Contains Duplicate Easy242 Valid Anagram Easy268 Missing Number Easy347 Top K Frequent Elements Medium424 Longest Repeating Character Replacement Medium621 Task Scheduler Medium781 Rabbits in Forest Medium804 Unique Morse Code Words Easy929 Unique Email Addresses Easy1763 Longest Nice Substring Easy1938 Maximum Genetic Difference Query Hard2325 Decode the Message Easy2421 Number of Good Paths Hard3120 Count the Number of Special Characters I Easy3311 Construct 2D Grid Matching Graph Layout Hard3327 Check if DFS Strings Are Palindromes Hard3531 Count Covered Buildings Medium
All Hash Table problems
1 Two Sum Easy3 Longest Substring Without Repeating Characters Medium12 Integer to Roman Medium13 Roman to Integer Easy17 Letter Combinations of a Phone Number Medium30 Substring with Concatenation of All Words Hard36 Valid Sudoku Medium37 Sudoku Solver Hard41 First Missing Positive Hard49 Group Anagrams Medium73 Set Matrix Zeroes Medium76 Minimum Window Substring Hard105 Construct Binary Tree from Preorder and Inorder Traversal Medium106 Construct Binary Tree from Inorder and Postorder Traversal Medium126 Word Ladder II Hard127 Word Ladder Hard128 Longest Consecutive Sequence Medium133 Clone Graph Medium138 Copy List with Random Pointer Medium139 Word Break Medium140 Word Break II Hard141 Linked List Cycle Easy142 Linked List Cycle II Medium146 LRU Cache Medium149 Max Points on a Line Hard160 Intersection of Two Linked Lists Easy166 Fraction to Recurring Decimal Medium169 Majority Element Easy187 Repeated DNA Sequences Medium202 Happy Number Easy205 Isomorphic Strings Easy208 Implement Trie (Prefix Tree) Medium217 Contains Duplicate Easy219 Contains Duplicate II Easy229 Majority Element II Medium242 Valid Anagram Easy264 Ugly Number II Medium268 Missing Number Easy290 Word Pattern Easy299 Bulls and Cows Medium336 Palindrome Pairs Hard347 Top K Frequent Elements Medium349 Intersection of Two Arrays Easy350 Intersection of Two Arrays II Easy355 Design Twitter Medium380 Insert Delete GetRandom O(1) Medium381 Insert Delete GetRandom O(1) - Duplicates allowed Hard383 Ransom Note Easy387 First Unique Character in a String Easy389 Find the Difference Easy391 Perfect Rectangle Hard395 Longest Substring with At Least K Repeating Characters Medium398 Random Pick Index Medium409 Longest Palindrome Easy421 Maximum XOR of Two Numbers in an Array Medium423 Reconstruct Original Digits from English Medium424 Longest Repeating Character Replacement Medium432 All O`one Data Structure Hard433 Minimum Genetic Mutation Medium438 Find All Anagrams in a String Medium442 Find All Duplicates in an Array Medium447 Number of Boomerangs Medium448 Find All Numbers Disappeared in an Array Easy451 Sort Characters By Frequency Medium454 4Sum II Medium457 Circular Array Loop Medium460 LFU Cache Hard480 Sliding Window Median Hard491 Non-decreasing Subsequences Medium496 Next Greater Element I Easy500 Keyboard Row Easy508 Most Frequent Subtree Sum Medium519 Random Flip Matrix Medium522 Longest Uncommon Subsequence II Medium523 Continuous Subarray Sum Medium525 Contiguous Array Medium532 K-diff Pairs in an Array Medium535 Encode and Decode TinyURL Medium554 Brick Wall Medium560 Subarray Sum Equals K Medium567 Permutation in String Medium575 Distribute Candies Easy594 Longest Harmonious Subsequence Easy599 Minimum Index Sum of Two Lists Easy609 Find Duplicate File in System Medium621 Task Scheduler Medium632 Smallest Range Covering Elements from K Lists Hard645 Set Mismatch Easy648 Replace Words Medium652 Find Duplicate Subtrees Medium653 Two Sum IV - Input is a BST Easy659 Split Array into Consecutive Subsequences Medium676 Implement Magic Dictionary Medium677 Map Sum Pairs Medium690 Employee Importance Medium691 Stickers to Spell Word Hard692 Top K Frequent Words Medium697 Degree of an Array Easy705 Design HashSet Easy706 Design HashMap Easy710 Random Pick with Blacklist Hard720 Longest Word in Dictionary Medium721 Accounts Merge Medium726 Number of Atoms Hard736 Parse Lisp Expression Hard740 Delete and Earn Medium745 Prefix and Suffix Search Hard748 Shortest Completing Word Easy752 Open the Lock Medium763 Partition Labels Medium767 Reorganize String Medium770 Basic Calculator IV Hard771 Jewels and Stones Easy781 Rabbits in Forest Medium791 Custom Sort String Medium792 Number of Matching Subsequences Medium804 Unique Morse Code Words Easy811 Subdomain Visit Count Medium815 Bus Routes Hard817 Linked List Components Medium819 Most Common Word Easy820 Short Encoding of Words Medium822 Card Flipping Game Medium823 Binary Trees With Factors Medium828 Count Unique Characters of All Substrings of a Given String Hard833 Find And Replace in String Medium839 Similar String Groups Hard840 Magic Squares In Grid Medium846 Hand of Straights Medium854 K-Similar Strings Hard859 Buddy Strings Easy863 All Nodes Distance K in Binary Tree Medium865 Smallest Subtree with all the Deepest Nodes Medium869 Reordered Power of 2 Medium873 Length of Longest Fibonacci Subsequence Medium874 Walking Robot Simulation Medium884 Uncommon Words from Two Sentences Easy888 Fair Candy Swap Easy889 Construct Binary Tree from Preorder and Postorder Traversal Medium890 Find and Replace Pattern Medium893 Groups of Special-Equivalent Strings Medium895 Maximum Frequency Stack Hard904 Fruit Into Baskets Medium911 Online Election Medium914 X of a Kind in a Deck of Cards Easy916 Word Subsets Medium923 3Sum With Multiplicity Medium924 Minimize Malware Spread Hard928 Minimize Malware Spread II Hard929 Unique Email Addresses Easy930 Binary Subarrays With Sum Medium939 Minimum Area Rectangle Medium947 Most Stones Removed with Same Row or Column Medium952 Largest Component Size by Common Factor Hard953 Verifying an Alien Dictionary Easy954 Array of Doubled Pairs Medium957 Prison Cells After N Days Medium959 Regions Cut By Slashes Medium961 N-Repeated Element in Size 2N Array Easy963 Minimum Area Rectangle II Medium966 Vowel Spellchecker Medium970 Powerful Integers Medium974 Subarray Sums Divisible by K Medium981 Time Based Key-Value Store Medium982 Triples with Bitwise AND Equal To Zero Hard987 Vertical Order Traversal of a Binary Tree Hard992 Subarrays with K Different Integers Hard996 Number of Squareful Arrays Hard997 Find the Town Judge Easy1001 Grid Illumination Hard1002 Find Common Characters Easy1010 Pairs of Songs With Total Durations Divisible by 60 Medium1015 Smallest Integer Divisible by K Medium1016 Binary String With Substrings Representing 1 To N Medium1027 Longest Arithmetic Subsequence Medium1036 Escape a Large Maze Hard1048 Longest String Chain Medium1054 Distant Barcodes Medium1072 Flip Columns For Maximum Number of Equal Rows Medium1074 Number of Submatrices That Sum to Target Hard1079 Letter Tile Possibilities Medium1090 Largest Values From Labels Medium1110 Delete Nodes And Return Forest Medium1122 Relative Sort Array Easy1123 Lowest Common Ancestor of Deepest Leaves Medium1124 Longest Well-Performing Interval Medium1128 Number of Equivalent Domino Pairs Easy1138 Alphabet Board Path Medium1146 Snapshot Array Medium1156 Swap For Longest Repeated Character Substring Medium1160 Find Words That Can Be Formed by Characters Easy1169 Invalid Transactions Medium1170 Compare Strings by Frequency of the Smallest Character Medium1171 Remove Zero Sum Consecutive Nodes from Linked List Medium1172 Dinner Plate Stacks Hard1177 Can Make Palindrome from Substring Medium1178 Number of Valid Words for Each Puzzle Hard1189 Maximum Number of Balloons Easy1202 Smallest String With Swaps Medium1207 Unique Number of Occurrences Easy1218 Longest Arithmetic Subsequence of Given Difference Medium1224 Maximum Equal Frequency Hard1248 Count Number of Nice Subarrays Medium1261 Find Elements in a Contaminated Binary Tree Medium1275 Find Winner on a Tic Tac Toe Game Easy1282 Group the People Given the Group Size They Belong To Medium1284 Minimum Number of Flips to Convert Binary Matrix to Zero Matrix Hard1296 Divide Array in Sets of K Consecutive Numbers Medium1297 Maximum Number of Occurrences of a Substring Medium1311 Get Watched Videos by Your Friends Medium1331 Rank Transform of an Array Easy1338 Reduce Array Size to The Half Medium1345 Jump Game IV Hard1346 Check If N and Its Double Exist Easy1347 Minimum Number of Steps to Make Two Strings Anagram Medium1348 Tweet Counts Per Frequency Medium1357 Apply Discount Every n Orders Medium1358 Number of Substrings Containing All Three Characters Medium1365 How Many Numbers Are Smaller Than the Current Number Easy1366 Rank Teams by Votes Medium1370 Increasing Decreasing String Easy1371 Find the Longest Substring Containing Vowels in Even Counts Medium1386 Cinema Seat Allocation Medium1394 Find Lucky Integer in an Array Easy1396 Design Underground System Medium1399 Count Largest Group Easy1400 Construct K Palindrome Strings Medium1410 HTML Entity Parser Medium1418 Display Table of Food Orders in a Restaurant Medium1436 Destination City Easy1442 Count Triplets That Can Form Two Arrays of Equal XOR Medium1443 Minimum Time to Collect All Apples in a Tree Medium1452 People Whose List of Favorite Companies Is Not a Subset of Another List Medium1460 Make Two Arrays Equal by Reversing Subarrays Easy1461 Check If a String Contains All Binary Codes of Size K Medium1477 Find Two Non-overlapping Sub-arrays Each With Target Sum Medium1481 Least Number of Unique Integers after K Removals Medium1487 Making File Names Unique Medium1488 Avoid Flood in The City Medium1496 Path Crossing Easy1497 Check If Array Pairs Are Divisible by k Medium1512 Number of Good Pairs Easy1519 Number of Nodes in the Sub-Tree With the Same Label Medium1525 Number of Good Ways to Split a String Medium1540 Can Convert String in K Moves Medium1542 Find Longest Awesome Substring Hard1546 Maximum Number of Non-Overlapping Subarrays With Sum Equals Target Medium1562 Find Latest Group of Size M Medium1577 Number of Ways Where Square of Number Is Equal to Product of Two Numbers Medium1590 Make Sum Divisible by P Medium1593 Split a String Into the Max Number of Unique Substrings Medium1600 Throne Inheritance Medium1604 Alert Using Same Key-Card Three or More Times in a One Hour Period Medium1624 Largest Substring Between Two Equal Characters Easy1630 Arithmetic Subarrays Medium1636 Sort Array by Increasing Frequency Easy1638 Count Substrings That Differ by One Character Medium1640 Check Array Formation Through Concatenation Easy1647 Minimum Deletions to Make Character Frequencies Unique Medium1656 Design an Ordered Stream Easy1657 Determine if Two Strings Are Close Medium1658 Minimum Operations to Reduce X to Zero Medium1674 Minimum Moves to Make Array Complementary Medium1679 Max Number of K-Sum Pairs Medium1684 Count the Number of Consistent Strings Easy1695 Maximum Erasure Value Medium1711 Count Good Meals Medium1713 Minimum Operations to Make a Subsequence Hard1726 Tuple with Same Product Medium1733 Minimum Number of People to Teach Medium1737 Change Minimum Characters to Satisfy One of Three Conditions Medium1742 Maximum Number of Balls in a Box Easy1743 Restore the Array From Adjacent Pairs Medium1748 Sum of Unique Elements Easy1763 Longest Nice Substring Easy1775 Equal Sum Arrays With Minimum Number of Operations Medium1781 Sum of Beauty of All Substrings Medium1782 Count Pairs Of Nodes Hard1790 Check if One String Swap Can Make Strings Equal Easy1796 Second Largest Digit in a String Easy1797 Design Authentication Manager Medium1805 Number of Different Integers in a String Easy1807 Evaluate the Bracket Pairs of a String Medium1814 Count Nice Pairs in an Array Medium1817 Finding the Users Active Minutes Medium1832 Check if the Sentence Is Pangram Easy1857 Largest Color Value in a Directed Graph Hard1865 Finding Pairs With a Certain Sum Medium1876 Substrings of Size Three with Distinct Characters Easy1893 Check if All the Integers in a Range Are Covered Easy1897 Redistribute Characters to Make All Strings Equal Easy1906 Minimum Absolute Difference Queries Medium1912 Design Movie Rental System Hard1915 Number of Wonderful Substrings Medium1930 Unique Length-3 Palindromic Subsequences Medium1932 Merge BSTs to Create Single BST Hard1935 Maximum Number of Words You Can Type Easy1938 Maximum Genetic Difference Query Hard1941 Check if All Characters Have Equal Number of Occurrences Easy1942 The Number of the Smallest Unoccupied Chair Medium1943 Describe the Painting Medium1948 Delete Duplicate Folders in System Hard1980 Find Unique Binary String Medium1993 Operations on Tree Medium1994 The Number of Good Subsets Hard1995 Count Special Quadruplets Easy2001 Number of Pairs of Interchangeable Rectangles Medium2006 Count Number of Pairs With Absolute Difference K Easy2007 Find Original Array From Doubled Array Medium2008 Maximum Earnings From Taxi Medium2009 Minimum Number of Operations to Make Array Continuous Hard2013 Detect Squares Medium2023 Number of Pairs of Strings With Concatenation Equal to Target Medium2025 Maximum Number of Ways to Partition an Array Hard2032 Two Out of Three Easy2034 Stock Price Fluctuation Medium2043 Simple Bank System Medium2048 Next Greater Numerically Balanced Number Medium2053 Kth Distinct String in an Array Easy2062 Count Vowel Substrings of a String Easy2068 Check Whether Two Strings are Almost Equivalent Easy2080 Range Frequency Queries Medium2085 Count Common Words With One Occurrence Easy2094 Finding 3-Digit Even Numbers Easy2099 Find Subsequence of Length K With the Largest Sum Easy2103 Rings and Rods Easy2115 Find All Possible Recipes from Given Supplies Medium2121 Intervals Between Identical Elements Medium2122 Recover the Original Array Hard2131 Longest Palindrome by Concatenating Two Letter Words Medium2133 Check if Every Row and Column Contains All Numbers Easy2135 Count Words Obtained After Adding a Letter Medium2150 Find All Lonely Numbers in the Array Medium2154 Keep Multiplying Found Values by Two Easy2166 Design Bitset Medium2170 Minimum Operations to Make the Array Alternating Medium2182 Construct String With Repeat Limit Medium2186 Minimum Number of Steps to Make Two Strings Anagram II Medium2190 Most Frequent Number Following Key In an Array Easy2196 Create Binary Tree From Descriptions Medium2201 Count Artifacts That Can Be Extracted Medium2206 Divide Array Into Equal Pairs Easy2215 Find the Difference of Two Arrays Easy2225 Find Players With Zero or One Losses Medium2227 Encrypt and Decrypt Strings Hard2244 Minimum Rounds to Complete All Tasks Medium2248 Intersection of Multiple Arrays Easy2249 Count Lattice Points Inside a Circle Medium2250 Count Number of Rectangles Containing Each Point Medium2251 Number of Flowers in Full Bloom Hard2260 Minimum Consecutive Cards to Pick Up Medium2261 K Divisible Elements Subarrays Medium2262 Total Appeal of A String Hard2266 Count Number of Texts Medium2273 Find Resultant Array After Removing Anagrams Easy2275 Largest Combination With Bitwise AND Greater Than Zero Medium2283 Check if Number Has Equal Digit Count and Digit Value Easy2284 Sender With Largest Word Count Medium2287 Rearrange Characters to Make Target String Easy2295 Replace Elements in an Array Medium2301 Match Substring After Replacement Hard2306 Naming a Company Hard2309 Greatest English Letter in Upper and Lower Case Easy2325 Decode the Message Easy2336 Smallest Number in Infinite Set Medium2341 Maximum Number of Pairs in Array Easy2342 Max Sum of a Pair With Equal Sum of Digits Medium2347 Best Poker Hand Easy2349 Design a Number Container System Medium2350 Shortest Impossible Sequence of Rolls Hard2351 First Letter to Appear Twice Easy2352 Equal Row and Column Pairs Medium2353 Design a Food Rating System Medium2354 Number of Excellent Pairs Hard2357 Make Array Zero by Subtracting Equal Amounts Easy2363 Merge Similar Items Easy2364 Count Number of Bad Pairs Medium2365 Task Scheduler II Medium2367 Number of Arithmetic Triplets Easy2368 Reachable Nodes With Restrictions Medium2370 Longest Ideal Subsequence Medium2374 Node With Highest Edge Score Medium2384 Largest Palindromic Number Medium2385 Amount of Time for Binary Tree to Be Infected Medium2395 Find Subarrays With Equal Sum Easy2399 Check Distances Between Same Letters Easy2402 Meeting Rooms III Hard2404 Most Frequent Even Element Easy2405 Optimal Partition of String Medium2418 Sort the People Easy2421 Number of Good Paths Hard2423 Remove Letter To Equalize Frequency Easy2424 Longest Uploaded Prefix Medium2434 Using a Robot to Print the Lexicographically Smallest String Medium2441 Largest Positive Integer That Exists With Its Negative Easy2442 Count Number of Distinct Integers After Reverse Operations Medium2451 Odd String Difference Easy2453 Destroy Sequential Targets Medium2456 Most Popular Video Creator Medium2461 Maximum Sum of Distinct Subarrays With Length K Medium2465 Number of Distinct Averages Easy2475 Number of Unequal Triplets in Array Easy2488 Count Subarrays With Median K Hard2491 Divide Players Into Teams of Equal Skill Medium2499 Minimum Total Cost to Make Arrays Unequal Hard2501 Longest Square Streak in an Array Medium2502 Design Memory Allocator Medium2506 Count Pairs Of Similar Strings Easy2508 Add Edges to Make Degrees of All Nodes Even Hard2512 Reward Top K Students Medium2514 Count Anagrams Hard2516 Take K of Each Character From Left and Right Medium2521 Distinct Prime Factors of Product of Array Medium2526 Find Consecutive Integers from a Data Stream Medium2531 Make Number of Distinct Characters Equal Medium2537 Count the Number of Good Subarrays Medium2540 Minimum Common Value Easy2547 Minimum Cost to Split an Array Hard2549 Count Distinct Numbers on Board Easy2554 Maximum Number of Integers to Choose From a Range I Medium2561 Rearranging Fruits Hard2564 Substring XOR Queries Medium2570 Merge Two 2D Arrays by Summing Values Easy2581 Count Number of Possible Root Nodes Hard2584 Split the Array to Make Coprime Products Hard2588 Count the Number of Beautiful Subarrays Medium2593 Find Score of an Array After Marking All Elements Medium2597 The Number of Beautiful Subsets Medium2598 Smallest Missing Non-negative Integer After Operations Medium2605 Form Smallest Number From Two Digit Arrays Easy2606 Find the Substring With Maximum Cost Medium2610 Convert an Array Into a 2D Array With Conditions Medium2615 Sum of Distances Medium2641 Cousins in Binary Tree II Medium2653 Sliding Subarray Beauty Medium2657 Find the Prefix Common Array of Two Arrays Medium2661 First Completely Painted Row or Column Medium2670 Find the Distinct Difference Array Easy2671 Frequency Tracker Medium2682 Find the Losers of the Circular Game Easy2707 Extra Characters in a String Medium2711 Difference of Number of Distinct Values on Diagonals Medium2713 Maximum Strictly Increasing Cells in a Matrix Hard2716 Minimize String Length Easy2718 Sum of Matrix After Queries Medium2729 Check if The Number is Fascinating Easy2732 Find a Good Subset of the Matrix Hard2744 Find Maximum Number of String Pairs Easy2747 Count Zero Request Servers Medium2748 Number of Beautiful Pairs Easy2763 Sum of Imbalance Numbers of All Subarrays Hard2766 Relocate Marbles Medium2767 Partition String Into Minimum Beautiful Substrings Medium2768 Number of Black Blocks Medium2780 Minimum Index of a Valid Split Medium2781 Length of the Longest Valid Substring Hard2784 Check if Array is Good Easy2799 Count Complete Subarrays in an Array Medium2808 Minimum Seconds to Equalize a Circular Array Medium2813 Maximum Elegance of a K-Length Subsequence Hard2815 Max Pair Sum in an Array Easy2830 Maximize the Profit as the Salesman Medium2831 Find the Longest Equal Subarray Medium2840 Check if Strings Can be Made Equal With Operations II Medium2841 Maximum Sum of Almost Unique Subarray Medium2842 Count K-Subsequences of a String With Maximum Beauty Hard2845 Count of Interesting Subarrays Medium2848 Points That Intersect With Cars Easy2856 Minimum Array Length After Pair Removals Medium2857 Count Pairs of Points With Distance k Medium2869 Minimum Operations to Collect Elements Easy2870 Minimum Number of Operations to Make Array Empty Medium2875 Minimum Size Subarray in Infinite Array Medium2897 Apply Operations on Array to Maximize Sum of Squares Hard2902 Count of Sub-Multisets With Bounded Sum Hard2910 Minimum Number of Groups to Create a Valid Assignment Medium2913 Subarrays Distinct Element Sum of Squares I Easy2932 Maximum Strong Pair XOR I Easy2933 High-Access Employees Medium2935 Maximum Strong Pair XOR II Hard2947 Count Beautiful Substrings I Medium2949 Count Beautiful Substrings II Hard2953 Count Complete Substrings Hard2956 Find Common Elements Between Two Arrays Easy2958 Length of Longest Subarray With at Most K Frequency Medium2963 Count the Number of Good Partitions Hard2965 Find Missing and Repeated Values Easy2975 Maximum Square Area by Removing Fences From a Field Medium2981 Find Longest Special Substring That Occurs Thrice I Medium2982 Find Longest Special Substring That Occurs Thrice II Medium2983 Palindrome Rearrangement Queries Hard2996 Smallest Missing Integer Greater Than Sequential Prefix Sum Easy3002 Maximum Size of a Set After Removals Medium3005 Count Elements With Maximum Frequency Easy3013 Divide an Array Into Subarrays With Minimum Cost II Hard3016 Minimum Number of Pushes to Type Word II Medium3020 Find the Maximum Number of Elements in Subset Medium3026 Maximum Good Subarray Sum Medium3035 Maximum Palindromes After Operations Medium3039 Apply Operations to Make String Empty Medium3043 Find the Length of the Longest Common Prefix Medium3044 Most Frequent Prime Medium3046 Split the Array Easy3071 Minimum Operations to Write the Letter Y on a Grid Medium3076 Shortest Uncommon Substring in an Array Medium3080 Mark Elements on Array by Performing Queries Medium3081 Replace Question Marks in String to Minimize Its Value Medium3083 Existence of a Substring in a String and Its Reverse Easy3085 Minimum Deletions to Make String K-Special Medium3090 Maximum Length Substring With Two Occurrences Easy3092 Most Frequent IDs Medium3120 Count the Number of Special Characters I Easy3121 Count the Number of Special Characters II Medium3128 Right Triangles Medium3134 Find the Median of the Uniqueness Array Hard3137 Minimum Number of Operations to Make Word K-Periodic Medium3138 Minimum Length of Anagram Concatenation Medium3143 Maximum Points Inside the Square Medium3144 Minimum Substring Partition of Equal Character Frequency Medium3146 Permutation Difference between Two Strings Easy3153 Sum of Digit Differences of All Pairs Medium3158 Find the XOR of Numbers Which Appear Twice Easy3159 Find Occurrences of an Element in an Array Medium3160 Find the Number of Distinct Colors Among the Balls Medium3162 Find the Number of Good Pairs I Easy3164 Find the Number of Good Pairs II Medium3170 Lexicographically Minimum String After Removing Stars Medium3176 Find the Maximum Length of a Good Subsequence I Medium3177 Find the Maximum Length of a Good Subsequence II Hard3184 Count Pairs That Form a Complete Day I Easy3185 Count Pairs That Form a Complete Day II Medium3186 Maximum Total Damage With Spell Casting Medium3217 Delete Nodes From Linked List Present in Array Medium3223 Minimum Length of String After Operations Medium3224 Minimum Array Changes to Make Differences Equal Medium3238 Find the Number of Winning Players Easy3242 Design Neighbor Sum Service Easy3265 Count Almost Equal Pairs I Medium3267 Count Almost Equal Pairs II Hard3272 Find the Count of Good Integers Hard3289 The Two Sneaky Numbers of Digitville Easy3295 Report Spam Message Medium3297 Count Substrings That Can Be Rearranged to Contain a String I Medium3298 Count Substrings That Can Be Rearranged to Contain a String II Hard3305 Count of Substrings Containing Every Vowel and K Consonants I Medium3306 Count of Substrings Containing Every Vowel and K Consonants II Medium3311 Construct 2D Grid Matching Graph Layout Hard3312 Sorted GCD Pair Queries Hard3316 Find Maximum Removals From Source String Medium3318 Find X-Sum of All K-Long Subarrays I Easy3321 Find X-Sum of All K-Long Subarrays II Hard3325 Count Substrings With K-Frequency Characters I Medium3327 Check if DFS Strings Are Palindromes Hard3331 Find Subtree Sizes After Changes Medium3335 Total Characters in String After Transformations I Medium3337 Total Characters in String After Transformations II Hard3351 Sum of Good Subsequences Hard3365 Rearrange K Substrings to Form Target String Medium3371 Identify the Largest Outlier in an Array Medium3375 Minimum Operations to Make Array Values Equal to K Easy3378 Count Connected Components in LCM Graph Hard3381 Maximum Subarray Sum With Length Divisible by K Medium3389 Minimum Operations to Make Character Frequencies Equal Hard3395 Subsequences with a Unique Middle Mode I Hard3396 Minimum Number of Operations to Make Elements in Array Distinct Easy3404 Count Special Subsequences Medium3408 Design Task Manager Medium3412 Find Mirror Score of a String Medium3425 Longest Special Path Hard3434 Maximum Frequency After Subarray Operation Medium3438 Find Valid Pair of Adjacent Digits in String Easy3442 Maximum Difference Between Even and Odd Frequency I Easy3443 Maximum Manhattan Distance After K Changes Medium3447 Assign Elements to Groups with Constraints Medium3458 Select K Disjoint Special Substrings Medium3471 Find the Largest Almost Missing Integer Easy3483 Unique 3-Digit Even Numbers Easy3484 Design Spreadsheet Medium3486 Longest Special Path II Hard3487 Maximum Unique Subarray Sum After Deletion Easy3488 Closest Equal Element Queries Medium3493 Properties Graph Medium3505 Minimum Operations to Make Elements Within K Subarrays Equal Hard3507 Minimum Pair Removal to Sort Array I Easy3508 Implement Router Medium3509 Maximum Product of Subsequences With an Alternating Sum Equal to K Hard3510 Minimum Pair Removal to Sort Array II Hard3518 Smallest Palindromic Rearrangement II Hard3522 Calculate Score After Performing Instructions Medium3527 Find the Most Common Response Medium3531 Count Covered Buildings Medium3532 Path Existence Queries in a Graph I Medium3541 Find Most Frequent Vowel and Consonant Easy3542 Minimum Operations to Convert All Elements to Zero Medium3543 Maximum Weighted K-Edge Path Medium3545 Minimum Deletions for At Most K Distinct Characters Easy3548 Equal Sum Grid Partition II Hard3551 Minimum Swaps to Sort by Digit Sum Medium3552 Grid Teleportation Traversal Medium3556 Sum of Largest Prime Substrings Medium3557 Find Maximum Number of Non Intersecting Substrings Medium3568 Minimum Moves to Clean the Classroom Medium3572 Maximize Y‑Sum by Picking a Triplet of Distinct X‑Values Medium3583 Count Special Triplets Medium3588 Find Maximum Area of a Triangle Medium3591 Check if Any Element Has Prime Frequency Easy3597 Partition String Medium3606 Coupon Code Validator Easy3607 Power Grid Maintenance Medium3623 Count Number of Trapezoids I Medium3625 Count Number of Trapezoids II Hard