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Study plan
Study Plan
Complete and win badges
Array1051
String511
Hash Table363
Dynamic Programming355
Math349
Depth-First Search238
Sorting234
Greedy227
Database195
Breadth-First Search192
Tree184
Binary Search170
Matrix159
Binary Tree155
Two Pointers143
Bit Manipulation128
Stack119
Design105
Heap (Priority Queue)103
Backtracking90
Graph89
Simulation88
Prefix Sum76
Counting69
Sliding Window69
Linked List66
Union Find59
Recursion42
Ordered Set40
Monotonic Stack40
Binary Search Tree40
Trie39
Divide and Conquer38
Bitmask33
Queue31
Enumeration28
Geometry28
Memoization28
Game Theory24
Segment Tree23
Hash Function22
Topological Sort22
Interactive18
Binary Indexed Tree17
Data Stream16
String Matching15
Rolling Hash15
Shortest Path13
Randomized12
Combinatorics12
Number Theory11
Monotonic Queue9
Iterator9
Merge Sort9
Concurrency9
Brainteaser8
Probability and Statistics7
Doubly-Linked List7
Quickselect6
Bucket Sort6
Minimum Spanning Tree5
Counting Sort5
Suffix Array5
Shell4
Line Sweep4
Reservoir Sampling4
Eulerian Circuit3
Strongly Connected Component2
Radix Sort2
Rejection Sampling2
Biconnected Component1
Expand
All Topics
Algorithms
Database
Shell
Concurrency
Status
Title
Company
Solution
Acceptance
Difficulty
Frequency
1. Two Sum
48.3%
Easy
2. Add Two Numbers
37.9%
Medium
3. Longest Substring Without Repeating Characters
32.9%
Medium
4. Median of Two Sorted Arrays
33.7%
Hard
5. Longest Palindromic Substring
31.7%
Medium
6. Zigzag Conversion
41.0%
Medium
7. Reverse Integer
26.5%
Medium
8. String to Integer (atoi)
16.5%
Medium
9. Palindrome Number
52.2%
Easy
10. Regular Expression Matching
28.2%
Hard
11. Container With Most Water
53.4%
Medium
12. Integer to Roman
59.1%
Medium
13. Roman to Integer
57.9%
Easy
14. Longest Common Prefix
39.0%
Easy
15. 3Sum
30.6%
Medium
16. 3Sum Closest
47.0%
Medium
17. Letter Combinations of a Phone Number
53.1%
Medium
18. 4Sum
37.0%
Medium
19. Remove Nth Node From End of List
37.9%
Medium
20. Valid Parentheses
40.6%
Easy
21. Merge Two Sorted Lists
59.4%
Easy
22. Generate Parentheses
69.4%
Medium
23. Merge k Sorted Lists
46.5%
Hard
24. Swap Nodes in Pairs
58.1%
Medium
25. Reverse Nodes in k-Group
50.3%
Hard
26. Remove Duplicates from Sorted Array
48.3%
Easy
27. Remove Element
50.9%
Easy
28. Implement strStr()
35.6%
Easy
29. Divide Two Integers
17.0%
Medium
30. Substring with Concatenation of All Words
27.8%
Hard
31. Next Permutation
35.3%
Medium
32. Longest Valid Parentheses
31.1%
Hard
33. Search in Rotated Sorted Array
37.5%
Medium
34. Find First and Last Position of Element in Sorted Array
39.7%
Medium
35. Search Insert Position
42.5%
Easy
36. Valid Sudoku
54.5%
Medium
37. Sudoku Solver
53.0%
Hard
38. Count and Say
48.3%
Medium
39. Combination Sum
64.7%
Medium
40. Combination Sum II
52.1%
Medium
41. First Missing Positive
35.7%
Hard
42. Trapping Rain Water
55.8%
Hard
43. Multiply Strings
37.4%
Medium
44. Wildcard Matching
26.4%
Hard
45. Jump Game II
36.5%
Medium
46. Permutations
71.4%
Medium
47. Permutations II
53.4%
Medium
48. Rotate Image
65.7%
Medium
49. Group Anagrams
63.5%
Medium
50. Pow(x, n)
32.1%
Medium
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