Hash Table (89 completed) Back to top # Title Level Cats Solution Languages Date Complete 1 Two Sum Easy N150, B75 solution py, java May 22, 2024 3 Longest Substring Without Repeating Characters Medium N150, B75 solution java May 22, 2024 36 Valid Sudoku Medium N150 solution py Jun 13, 2024 49 Group Anagrams Medium N150, B75 solution py Jun 12, 2024 128 Longest Consecutive Sequence Medium N150, B75 solution py, java Jun 12, 2024 138 Copy List with Random Pointer Medium N150 solution py Jun 27, 2024 141 Linked List Cycle Easy N150, B75 solution py, c Jun 03, 2024 142 Linked List Cycle II Medium solution py Jun 25, 2024 166 Fraction to Recurring Decimal Medium solution py May 31, 2024 208 Implement Trie (Prefix Tree) Medium N150, B75 solution py Jun 27, 2024 217 Contains Duplicate Easy N150, B75 solution py Jun 11, 2024 242 Valid Anagram Easy N150, B75 solution py, c Jun 12, 2024 314 Binary Tree Vertical Order Traversal Medium solution py Jun 11, 2024 347 Top K Frequent Elements Medium N150, B75 solution py Jun 12, 2024 348 Design Tic-Tac-Toe Medium solution py Jul 04, 2024 350 Intersection of Two Arrays II Easy Daily solution py, java Jul 01, 2024 353 Design Snake Game Medium solution py Jun 28, 2024 380 Insert Delete GetRandom O(1) Medium solution java Jul 05, 2024 381 Insert Delete GetRandom O(1) - Duplicates allowed Hard solution java Jul 05, 2024 409 Longest Palindrome Easy Daily solution py, c Jun 03, 2024 424 Longest Repeating Character Replacement Medium N150, B75 solution py Jul 05, 2024 451 Sort Characters By Frequency Medium solution py Jun 17, 2024 523 Continuous Subarray Sum Medium Daily solution py Jun 08, 2024 535 Encode and Decode TinyURL Medium solution py Jun 07, 2024 567 Permutation in String Medium N150 solution py Jul 05, 2024 616 Add Bold Tag in String Medium solution py Jun 27, 2024 645 Set Mismatch Easy solution py, java Jun 01, 2024 648 Replace Words Medium Daily solution py, java Jun 06, 2024 666 Path Sum IV Medium solution py Jul 03, 2024 676 Implement Magic Dictionary Medium solution py Jun 27, 2024 690 Employee Importance Medium solution java Jul 02, 2024 692 Top K Frequent Words Medium solution py Jun 08, 2024 720 Longest Word in Dictionary Medium solution py Jun 27, 2024 758 Bold Words in String Medium solution py Jun 27, 2024 771 Jewels and Stones Easy solution py, java Jun 02, 2024 791 Custom Sort String Medium solution java Jun 24, 2024 817 Linked List Components Medium solution java Jul 04, 2024 846 Hand of Straights Medium N150, Daily solution py Jun 06, 2024 863 All Nodes Distance K in Binary Tree Medium solution py Jun 26, 2024 890 Find and Replace Pattern Medium solution py Jul 02, 2024 930 Binary Subarrays With Sum Medium solution py Jun 21, 2024 974 Subarray Sums Divisible by K Medium Daily solution py, java Jun 09, 2024 987 Vertical Order Traversal of a Binary Tree Hard solution py Jun 11, 2024 1002 Find Common Characters Easy Daily solution py Jun 04, 2024 1122 Relative Sort Array Easy Daily solution py, java Jun 10, 2024 1166 Design File System Medium solution py Jun 27, 2024 1171 Remove Zero Sum Consecutive Nodes from Linked List Medium solution py Jun 15, 2024 1218 Longest Arithmetic Subsequence of Given Difference Medium solution py May 31, 2024 1248 Count Number of Nice Subarrays Medium Daily solution py Jun 21, 2024 1282 Group the People Given the Group Size They Belong To Medium solution py Jun 27, 2024 1284 Minimum Number of Flips to Convert Binary Matrix to Zero Matrix Hard solution py Jun 08, 2024 1426 Counting Elements Easy solution c Jun 04, 2024 1436 Destination City Easy solution java Jun 01, 2024 1442 Count Triplets That Can Form Two Arrays of Equal XOR Medium Daily solution py May 29, 2024 1460 Make Two Arrays Equal by Reversing Subarrays Easy solution c Jun 04, 2024 1481 Least Number of Unique Integers after K Removals Medium solution py Jun 15, 2024 1490 Clone N-ary Tree Medium solution py, java Jun 01, 2024 1525 Number of Good Ways to Split a String Medium solution py Jun 01, 2024 1570 Dot Product of Two Sparse Vectors Medium solution py, java, c Jun 06, 2024 1650 Lowest Common Ancestor of a Binary Tree III Medium solution py Jun 09, 2024 1660 Correct a Binary Tree Medium solution py Jun 26, 2024 1676 Lowest Common Ancestor of a Binary Tree IV Medium solution py Jun 29, 2024 1684 Count the Number of Consistent Strings Easy solution py, c Jun 06, 2024 1743 Restore the Array From Adjacent Pairs Medium solution py Jun 26, 2024 1748 Sum of Unique Elements Easy solution c Jun 06, 2024 1804 Implement Trie II (Prefix Tree) Medium solution py Jun 27, 2024 1836 Remove Duplicates From an Unsorted Linked List Medium solution py Jul 04, 2024 1852 Distinct Numbers in Each Subarray Medium solution java Jun 26, 2024 1940 Longest Common Subsequence Between Sorted Arrays Medium Weekly Premium solution py, java Jun 01, 2024 1980 Find Unique Binary String Medium solution py, c Jun 26, 2024 2013 Detect Squares Medium N150 solution py Jun 28, 2024 2083 Substrings That Begin and End With the Same Letter Medium Weekly Premium solution py, c Jun 10, 2024 2206 Divide Array Into Equal Pairs Easy solution py, c Jun 08, 2024 2225 Find Players With Zero or One Losses Medium solution java Jun 24, 2024 2248 Intersection of Multiple Arrays Easy solution py May 29, 2024 2268 Minimum Number of Keypresses Medium solution py Jul 05, 2024 2352 Equal Row and Column Pairs Medium solution py Jun 26, 2024 2365 Task Scheduler II Medium solution py Jun 29, 2024 2374 Node With Highest Edge Score Medium solution py Jun 17, 2024 2385 Amount of Time for Binary Tree to Be Infected Medium solution py Jun 26, 2024 2395 Find Subarrays With Equal Sum Easy solution py May 30, 2024 2405 Optimal Partition of String Medium solution py Jun 23, 2024 2423 Remove Letter To Equalize Frequency Easy solution py Jun 16, 2024 2570 Merge Two 2D Arrays by Summing Values Easy solution c Jun 10, 2024 2610 Convert an Array Into a 2D Array With Conditions Medium solution py Jun 07, 2024 2671 Frequency Tracker Medium solution py Jun 28, 2024 2743 Count Substrings Without Repeating Character Medium Weekly Premium solution py, java Jun 21, 2024 3043 Find the Length of the Longest Common Prefix Medium solution py Jun 27, 2024 3174 bw contest 132 - q1 Easy Contest solution py Jun 08, 2024