Hash Table

No.	Title	Solution	Difficulty	TimeComplexity	SpaceComplexity	Favorite	Acceptance
0001	Two Sum		Easy	O(n)	O(n)		46.3%
0003	Longest Substring Without Repeating Characters		Medium	O(n)	O(1)	❤️	31.3%
0018	4Sum		Medium	O(n^3)	O(n^2)	❤️	34.7%
0030	Substring with Concatenation of All Words		Hard	O(n)	O(n)	❤️	26.1%
0036	Valid Sudoku		Medium	O(n^2)	O(n^2)		50.3%
0037	Sudoku Solver		Hard	O(n^2)	O(n^2)	❤️	46.1%
0049	Group Anagrams		Medium	O(n log n)	O(n)		58.9%
0076	Minimum Window Substring		Hard	O(n)	O(n)	❤️	35.8%
0094	Binary Tree Inorder Traversal		Medium	O(n)	O(1)		65.5%
0136	Single Number		Easy				66.4%
0138	Copy List with Random Pointer		Medium	O(n)	O(1)		39.6%
0187	Repeated DNA Sequences		Medium				41.3%
0202	Happy Number		Easy	O(log n)	O(1)		51.1%
0204	Count Primes		Easy				32.1%
0205	Isomorphic Strings		Easy	O(log n)	O(n)		40.4%
0217	Contains Duplicate		Easy	O(n)	O(n)		56.5%
0219	Contains Duplicate II		Easy	O(n)	O(n)		38.5%
0242	Valid Anagram		Easy	O(n)	O(n)		58.0%
0274	H-Index		Medium	O(n)	O(n)		36.3%
0290	Word Pattern		Easy	O(n)	O(n)		38.3%
0347	Top K Frequent Elements		Medium	O(n)	O(n)		62.2%
0349	Intersection of Two Arrays		Easy	O(n)	O(n)		64.5%
0350	Intersection of Two Arrays II		Easy	O(n)	O(n)		51.9%
0387	First Unique Character in a String		Easy				53.7%
0389	Find the Difference		Easy				57.7%
0409	Longest Palindrome		Easy				52.2%
0438	Find All Anagrams in a String		Medium	O(n)	O(1)		44.7%
0447	Number of Boomerangs		Medium	O(n)	O(1)		52.4%
0451	Sort Characters By Frequency		Medium	O(n log n)	O(1)		64.2%
0454	4Sum II		Medium	O(n^2)	O(n)		54.5%
0463	Island Perimeter		Easy				66.6%
0500	Keyboard Row		Easy				65.5%
0508	Most Frequent Subtree Sum		Medium				58.9%
0575	Distribute Candies		Easy				61.9%
0594	Longest Harmonious Subsequence		Easy				47.8%
0599	Minimum Index Sum of Two Lists		Easy				51.5%
0632	Smallest Range Covering Elements from K Lists		Hard				54.0%
0645	Set Mismatch		Easy				42.5%
0648	Replace Words		Medium	O(n)	O(n)		58.3%
0676	Implement Magic Dictionary		Medium	O(n)	O(n)		55.2%
0705	Design HashSet		Easy				64.6%
0706	Design HashMap		Easy				62.6%
0710	Random Pick with Blacklist		Hard	O(n)	O(n)		32.6%
0718	Maximum Length of Repeated Subarray		Medium				50.2%
0720	Longest Word in Dictionary		Easy	O(n)	O(n)		49.1%
0726	Number of Atoms		Hard	O(n)	O(n)	❤️	51.0%
0739	Daily Temperatures		Medium	O(n)	O(n)		64.4%
0748	Shortest Completing Word		Easy				57.4%
0771	Jewels and Stones		Easy				86.9%
0781	Rabbits in Forest		Medium				55.4%
0811	Subdomain Visit Count		Easy				71.2%
0884	Uncommon Words from Two Sentences		Easy				64.0%
0895	Maximum Frequency Stack		Hard	O(n)	O(n)		62.2%
0930	Binary Subarrays With Sum		Medium	O(n)	O(n)	❤️	44.3%
0953	Verifying an Alien Dictionary		Easy				52.4%
0961	N-Repeated Element in Size 2N Array		Easy				74.4%
0970	Powerful Integers		Easy				39.9%
0981	Time Based Key-Value Store		Medium				54.0%
0992	Subarrays with K Different Integers		Hard	O(n)	O(n)	❤️	50.5%
1002	Find Common Characters		Easy				68.2%
1078	Occurrences After Bigram		Easy				64.8%
1160	Find Words That Can Be Formed by Characters		Easy				67.6%
1189	Maximum Number of Balloons		Easy				61.7%
1207	Unique Number of Occurrences		Easy				71.6%
1512	Number of Good Pairs		Easy				87.8%
1539	Kth Missing Positive Number		Easy				55.2%
1640	Check Array Formation Through Concatenation		Easy				60.7%
1679	Max Number of K-Sum Pairs		Medium				54.3%
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