General Problems

Arrays

1. Count Inversions
2. Reverse Pairs

Heap

1. Min cost to combine Gold
2. Sort k-sorted Array

Dynamic Programming

Knapsack:
1. 0-1 Knapsack
2. Coin Change
3. Rod Cutting

Stocks:
1. Buy and Sell Stock
2. Buy and Sell Stocks 2
3. Buy and Sell Stocks 3

DP on Subsequences:
1. Longest Common Subsequence
2. Print Longest Common Subsequence
3. Longest Common Substring
4. Longest Common Palindromic Subsequence
5. Min Insertions to make Palindromic
6. Smallest Common Supersequence
7. Count Subset with target Sum

Trie

1. Trie Implementation
2. Trie with word, pref count

Stack

1. Shorten Mathematical Expression

Trees

Traversals:
1. Preorder
2. Inorder
3. Postorder
4. Levelorder

General:
1. Boundary View
2. Root to Node Path
3. Max Path Sum
4. Width of Binary Tree
5. Diameter of Binary Tree
6. Lowest Common Ancestor
7. Min Time to Burn Binary Tree

Graphs

1. Alien Dictionary
2. Shortest Path Unit Edges
3. Dijkstra’s Algorithm
4. Detect Cycle in Undirected Graph
5. Detect Cycle in Directed Graph
6. Topological Sort
7. Bipartite Graph
8. Prim’s Algorithm
9. Union Find
10. Kruskal’s Algorithm
11. Bridges in a Undirected Graph
12. Artiuculation Point
13. Kosaraju’s Algorithm
14. Bellman Ford’s Algorithm

Miscellaneous

1. Add two numbers