Backtracking is a general algorithm for finding all (or some) solutions to some computational problems.
Leetcode backtracking problem collection (1)
- 46.Permutations
- 78.Subsets
- 77.Combinations
- 39.Combination Sum
- 22.Generate Parentheses
Leetcode Tree problem collection (3)
- 99.Recover Binary Search Tree
- 94.Binary Tree Inorder Traversal
- 116.Populating Next Right Pointers in Each Node
- 114.Flatten Binary Tree to Linked List
- 654.Maximum Binary Tree
- 106.Construct Binary Tree from Inorder and Postorder Traversal
Basically, there’re two ways to store data strctures: array and linked list.
All other data strctures, such as queue, stack, graph, hashmap, tree, heap, etc, all can be implemented by array and linked list.
Leetcode Stack Problem Collection (1)
- 20.Valid Parentheses
- 1249.Minimum Remove to Make Valid Parentheses
- 394.Decode String
- 1209.Remove All Adjacent Duplicates in String II
- 739.Daily Temperatures
- Simplify Path
Leetcode Dynamic Programming Problem Collection (1)
Green hand in DP problem
The key of Dynamic Programming is to get local result, then get global result.
- 70.Climbing Stairs
- 121.Best Time to Buy and Sell Stock *
- 53.Maximum Subarray
- 198.House Robber
- 746.Min Cost Climbing Stairs
- 42.Trapping Rain Water
Leetcode Sorting Problem Collection (1)
- 56.Merge Intervals
- 253.Meeting Rooms II
- 973.K Closest Points to Origin
- 148.Sort List *
- 88.Merge Sorted Array
| Name | Time Complexity | Sapce Complexity |
|---|---|---|
| Bubble Sort | O(n^2) | O(1) |
| Selection Sort | O(n^2) | O(1) |
| Insertion Sort | O(n^2) | O(1) |
| Merge Sort | O(n log(n)) | O(n) |
| Quick Sort | O(n^2) | O(log(n)) |
| Heap Sort | O(n log(n)) | O(1) |
| Counting Sort | O(n+k) | O(k) |
| Radix Sort | O(nk) | O(n+k) |
Leetcode Tree problem collection (2)
- 199.Binary Tree Right Side View
- 105.Construct Binary Tree from Preorder and Inorder Traversal
- 236.Lowest Common Ancestor of a Binary Tree
- 987.Vertical Order Traversal of a Binary Tree
- 103.Binary Tree Zigzag Level Order Traversal
Leetcode Tree problem collection (1)
- 104.Maximum Depth of Binary Tree
- 98.Validate Binary Search Tree
- 101.Symmetric Tree
- 102.Binary Tree Level Order Traversal
- 108.Convert Sorted Array to Binary Search Tree
Inorder (Left, Root, Right)
Preorder (Root, Left, Right)
Postorder (Left, Right, Root)
Leetcode linked list problem collection (1)
- 19.Remove Nth Node From End of List
- 206.Reverse Linked List
- 21.Merge Two Sorted Lists
- 234.Palindrome Linked List
- 141.Linked List Cycle
- 203.Remove Linked List Elements
- 83.Remove Duplicates from Sorted List
- 2.Add Two Numbers
- 876.Middle of the Linked List
- 369.Plus One Linked List