Coding Problems

27 problems

My notes on coding problems, grouped by category. Each problem has the description, the idea behind a solution, and pseudo-code.

Categories

Array 8 Backtracking 2 BFS 1 Binary Search 4 Divide and Conquer 3 Dynamic Programming 4 Graph 5 Heap 2 Matrix 3 Other 2 Sliding Window 2 Sorting 1 Tree 2 Two Pointers 3 Union-Find 1

All problems

#TitleDifficultyCategories
5 Longest Palindromic Substring Medium Two Pointers Dynamic Programming
15 3Sum Medium Two Pointers Array
33 Search in Rotated Sorted Array Medium Binary Search
34 Find First and Last Position of Element in Sorted Array Medium Array Binary Search
53 Maximum Subarray Medium Array Divide and Conquer
79 Word Search Medium Backtracking Matrix
105 Construct Binary Tree from Preorder and Inorder Traversal Medium Tree Divide and Conquer
106 Construct Binary Tree from Inorder and Postorder Traversal Medium Tree Divide and Conquer
128 Longest Consecutive Sequence Medium Array
134 Gas Station Medium Array
146 LRU Cache Medium Other
153 Find Minimum in Rotated Sorted Array Medium Binary Search
200 Number of Islands Medium Graph Matrix
207 Course Schedule Medium Graph
210 Course Schedule II Medium Graph BFS
215 Kth Largest Element in an Array Medium Heap Sorting
216 Combination Sum III Medium Backtracking
220 Contains Duplicate III Hard Array Sliding Window
253 Meeting Schedule II Medium Heap Array
300 Longest Increasing Subsequence Medium Dynamic Programming Binary Search
322 Coin Change Medium Dynamic Programming
394 Decode String Medium Other
723 Candy Crush Medium Matrix Two Pointers
785 Is Graph Bipartite? Medium Graph
790 Domino and Tromino Tiling Medium Dynamic Programming
1101 The Earliest Moment When Everyone Become Friends Medium Union-Find Graph
Delete k Elements to Balance Medium Sliding Window Array