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Hash Tables

25 problems 13 easy, 11 medium, 1 hard.

#TitleDifficultyFrequency
49Group Anagramsmediumcompany favorite
128Longest Consecutive Sequencemediumcompany favorite
167Two Sum II - Input Array Is Sortedmediumfoundational
202Happy Numbereasyfoundational
205Isomorphic Stringseasyfrequently asked
217Contains Duplicateeasyfoundational
242Valid Anagrameasyfoundational
290Word Patterneasycommon
347Top K Frequent Elementsmediumcompany favorite
350Intersection of Two Arrays IIeasyfoundational
380Insert Delete GetRandom O(1)mediumcompany favorite
381Insert Delete GetRandom O(1) - Duplicates allowedhardcompany favorite
383Ransom Noteeasyfoundational
387First Unique Character in a Stringeasyfoundational
409Longest Palindromeeasycommon
438Find All Anagrams in a Stringmediumfrequently asked
4544Sum IImediumfrequently asked
535Encode and Decode TinyURLmediumcommon
560Subarray Sum Equals Kmediumcompany favorite
705Design HashSeteasyfrequently asked
706Design HashMapeasyfrequently asked
811Subdomain Visit Countmediummedium
890Find and Replace Patternmediumcommon
929Unique Email Addresseseasyhigh
1207Unique Number of Occurrenceseasycommon