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1. Two Sum

2. Add Two Numbers

3. Longest Substring Without Repeating Characters

4. Median of Two Sorted Arrays

5. Longest Palindromic Substring

6. ZigZag Conversion

7. Reverse Integer

8. String to Integer (atoi)

9. Palindrome Number

10. Regular Expression Matching

11. Container With Most Water

12. Integer to Roman

13. Roman to Integer

14. Longest Common Prefix

15. 3Sum

16. 3Sum Closest

17. Letter Combinations of a Phone Number

19. Remove Nth Node From End of List

20. Valid Parentheses

21. Merge Two Sorted Lists

22. Generate Parentheses

23. Merge k Sorted Lists

24. Swap Nodes in Pairs

26. Remove Duplicates from Sorted Array

27. Remove Element

28. Implement strStr()

29. Divide Two Integers

31. Next Permutation

32. Longest Valid Parentheses

33. Search in Rotated Sorted Array

34. Find First and Last Position of Element in Sorted Array

35. Search Insert Position

36. Valid Sudoku

38. Count and Say

39. Combination Sum

40. Combination Sum II

41. First Missing Positive

43. Multiply Strings

45. Jump Game II

46. Permutations

47. Permutations II

48. Rotate Image

49. Group Anagrams

50. Pow(x, n)

53. Maximum Subarray

54. Spiral Matrix

55. Jump Game

56. Merge Intervals

57. Insert Interval

58. Length of Last Word

59. Spiral Matrix II

60. Permutation Sequence

61. Rotate List

62. Unique Paths

63. Unique Paths II

65. Valid Number

66. Plus One

67. Add Binary

68. Text Justification

69. Sqrt(x)

70. Climbing Stairs

71. Simplify Path

73. Set Matrix Zeroes

74. Search a 2D Matrix

75. Sort Colors

77. Combinations

78. Subsets

79. Word Search

80. Remove Duplicates from Sorted Array II

81. Search in Rotated Sorted Array II

82. Remove Duplicates from Sorted List II

83. Remove Duplicates from Sorted List

86. Partition List

88. Merge Sorted Array

92. Reverse Linked List II

93. Restore IP Addresses

94. Binary Tree Inorder Traversal

95. Unique Binary Search Trees II

96. Unique Binary Search Trees

98. Validate Binary Search Tree

99. Recover Binary Search Tree

100. Same Tree

101. Symmetric Tree

102. Binary Tree Level Order Traversal

103. Binary Tree Zigzag Level Order Traversal

104. Maximum Depth of Binary Tree

105. Construct Binary Tree from Preorder and Inorder Traversal

106. Construct Binary Tree from Inorder and Postorder Traversal

107. Binary Tree Level Order Traversal II

108. Convert Sorted Array to Binary Search Tree

109. Convert Sorted List to Binary Search Tree

110. Balanced Binary Tree

111. Minimum Depth of Binary Tree

112. Path Sum

113. Path Sum II

114. Flatten Binary Tree to Linked List

115. Distinct Subsequences

116. Populating Next Right Pointers in Each Node

117. Populating Next Right Pointers in Each Node II

118. Pascal's Triangle

119. Pascal's Triangle II

120. Triangle

121. Best Time to Buy and Sell Stock

122. Best Time to Buy and Sell Stock II

125. Valid Palindrome

129. Sum Root to Leaf Numbers

136. Single Number

141. Linked List Cycle

143. Reorder List

144. Binary Tree Preorder Traversal

145. Binary Tree Postorder Traversal

151. Reverse Words in a String

153. Find Minimum in Rotated Sorted Array

155. Min Stack

160. Intersection of Two Linked Lists

175. Combine Two Tables

176. Second Highest Salary

181. Employees Earning More Than Their Managers

182. Duplicate Emails

183. Customers Who Never Order

192. Word Frequency

195. Tenth Line

196. Delete Duplicate Emails

197. Rising Temperature

199. Binary Tree Right Side View

203. Remove Linked List Elements

206. Reverse Linked List

217. Contains Duplicate

222. Count Complete Tree Nodes

223. Rectangle Area

226. Invert Binary Tree

230. Kth Smallest Element in a BST

235. Lowest Common Ancestor of a Binary Search Tree

236. Lowest Common Ancestor of a Binary Tree

237. Delete Node in a Linked List

257. Binary Tree Paths

263. Ugly Number

278. First Bad Version

283. Move Zeroes

290. Word Pattern

292. Nim Game

299. Bulls and Cows

303. Range Sum Query - Immutable

326. Power of Three

328. Odd Even Linked List

342. Power of Four

344. Reverse String

345. Reverse Vowels of a String

383. Ransom Note

387. First Unique Character in a String

404. Sum of Left Leaves

434. Number of Segments in a String

445. Add Two Numbers II

501. Find Mode in Binary Search Tree

520. Detect Capital

541. Reverse String II

645. Set Mismatch

690. Employee Importance

704. Binary Search

705. Design HashSet

706. Design HashMap

707. Design Linked List

709. To Lower Case

725. Split Linked List in Parts

729. My Calendar I

766. Toeplitz Matrix

771. Jewels and Stones

781. Rabbits in Forest

784. Letter Case Permutation

796. Rotate String

804. Unique Morse Code Words

806. Number of Lines To Write String

811. Subdomain Visit Count

817. Linked List Components

825. Friends Of Appropriate Ages

830. Positions of Large Groups

832. Flipping an Image

835. Image Overlap

840. Magic Squares In Grid

849. Maximize Distance to Closest Person

867. Transpose Matrix

876. Middle of the Linked List

883. Projection Area of 3D Shapes

884. Uncommon Words from Two Sentences

892. Surface Area of 3D Shapes

896. Monotonic Array

1019. Next Greater Node In Linked List

1171. Remove Zero Sum Consecutive Nodes from Linked List

1185. Day of the Week

1200. Minimum Absolute Difference

1222. Queens That Can Attack the King

1232. Check If It Is a Straight Line

1290. Convert Binary Number in a Linked List to Integer

1367. Linked List in Binary Tree

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182. Duplicate Emails

#Easy#Database

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sql

sql

select Email from Person group by Email having count(*)>1

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