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Array2,209 String870 Hash Table786 Math682 Dynamic Programming666 Sorting504 Greedy480 Binary Search352 Depth-First Search335 Database303 Bit Manipulation283 Matrix278 Tree261 Breadth-First Search255 Two Pointers249 All topics

With video · 870 results

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TitleSolutionAcceptDifficultyTopics

3. Longest Substring Without Repeating CharactersVideo

Solution39.9%Medium

Hash Table, Sliding Window +1· 104 companies

5. Longest Palindromic SubstringVideo

Solution38.7%Medium

Dynamic Programming, String +1· 81 companies

6. Zigzag ConversionVideo

Solution54.9%Medium

String· 19 companies

8. String to Integer (atoi)Video

Solution21.4%Medium

String· 21 companies

10. Regular Expression MatchingVideo

Solution31.8%Hard

Dynamic Programming, Recursion +1· 25 companies

12. Integer to RomanVideo

Solution71.8%Medium

Hash Table, Math +1· 31 companies

13. Roman to IntegerVideo

Solution67.0%Easy

Hash Table, Math +1· 36 companies

14. Longest Common PrefixVideo

Solution48.6%Easy

String, Trie· 60 companies

17. Letter Combinations of a Phone NumberVideo

Solution66.9%Medium

Backtracking, Hash Table +1· 34 companies

20. Valid ParenthesesVideo

Solution45.2%Easy

Stack, String· 113 companies

22. Generate ParenthesesVideo

Solution79.6%Medium

Backtracking, Dynamic Programming +1· 40 companies

28. Find the Index of the First Occurrence in a StringVideo

Solution47.0%Easy

String, String Matching +1· 16 companies

30. Substring with Concatenation of All WordsVideo

Solution35.4%Hard

Hash Table, Sliding Window +1· 10 companies

32. Longest Valid ParenthesesVideo

Solution41.2%Hard

Dynamic Programming, Stack +1· 25 companies

38. Count and SayVideo

Solution63.7%Medium

String· 13 companies

43. Multiply StringsVideo

Solution44.4%Medium

Math, Simulation +1· 17 companies

44. Wildcard MatchingVideo

Solution32.8%Hard

Dynamic Programming, Greedy +2· 17 companies

49. Group AnagramsVideo

Solution73.0%Medium

Array, Hash Table +2· 87 companies

58. Length of Last WordVideo

Solution59.7%Easy

String· 7 companies

65. Valid NumberVideo

Solution23.3%Hard

String· 7 companies

67. Add BinaryVideo

Solution58.4%Easy

Bit Manipulation, Math +2· 17 companies

68. Text JustificationVideo

Solution52.4%Hard

Array, Simulation +1· 44 companies

71. Simplify PathVideo

Solution51.4%Medium

Stack, String· 24 companies

72. Edit DistanceVideo

Solution61.5%Medium

Dynamic Programming, String· 24 companies

76. Minimum Window SubstringVideo

Solution48.3%Hard

Hash Table, Sliding Window +1· 35 companies

79. Word SearchVideo

Solution48.2%Medium

Array, Backtracking +2· 36 companies

87. Scramble StringVideo

Solution45.9%Hard

Dynamic Programming, String· 6 companies

91. Decode WaysVideo

Solution38.3%Medium

Dynamic Programming, String· 22 companies

93. Restore IP AddressesVideo

Solution57.3%Medium

Backtracking, String· 20 companies

97. Interleaving StringVideo

Solution45.0%Medium

Dynamic Programming, String· 10 companies

115. Distinct SubsequencesVideo

Solution54.1%Hard

Dynamic Programming, String· 13 companies

125. Valid PalindromeVideo

Solution54.2%Easy

String, Two Pointers· 39 companies

126. Word Ladder IIVideo

Solution27.7%Hard

Backtracking, Breadth-First Search +2· 15 companies

127. Word LadderVideo

Solution46.3%Hard

Breadth-First Search, Hash Table +1· 41 companies

131. Palindrome PartitioningVideo

Solution74.4%Medium

Backtracking, Dynamic Programming +1· 10 companies

132. Palindrome Partitioning IIVideo

Solution37.9%Hard

Dynamic Programming, String· 9 companies

139. Word BreakVideo

Solution49.8%Medium

Array, Dynamic Programming +4· 32 companies

140. Word Break IIVideo

Solution56.4%Hard

Array, Backtracking +5· 16 companies

151. Reverse Words in a StringVideo

Solution57.8%Medium

String, Two Pointers· 30 companies

159. Longest Substring with At Most Two Distinct CharactersVideoPremium

Solution57.0%Medium

Hash Table, Sliding Window +1· 5 companies

161. One Edit DistanceVideoPremium

Solution34.4%Medium

String, Two Pointers· 8 companies

165. Compare Version NumbersVideo

Solution46.8%Medium

String, Two Pointers· 11 companies

166. Fraction to Recurring DecimalVideo

Solution31.3%Medium

Hash Table, Math +1· 10 companies

168. Excel Sheet Column TitleVideo

Solution47.9%Easy

Math, String· 10 companies

171. Excel Sheet Column NumberVideo

Solution68.6%Easy

Math, String· 9 companies

179. Largest NumberVideo

Solution43.9%Medium

Array, Greedy +2· 23 companies

186. Reverse Words in a String IIVideoPremium

Solution56.6%Medium

String, Two Pointers· 4 companies

187. Repeated DNA SequencesVideo

Solution53.7%Medium

Bit Manipulation, Hash Function +4· 7 companies

205. Isomorphic StringsVideo

Solution48.8%Easy

Hash Table, String· 15 companies

208. Implement Trie (Prefix Tree)Video

Solution69.9%Medium

Design, Hash Table +2· 21 companies

Showing 1–50 of 870