Gold
The topics below are not exhaustive for this division.
Contest problems may contain topics not covered in the guide, or topics listed under different divisions!
Modules Progress
Problems Progress
Introductory Number Sense
Dynamic Programming
Every (?) Gold and Platinum contest has at least one DP problem.
Introduction to DP
Very Frequent
Speeding up naive recursive solutions with memoization.
Knapsack DP
Not Frequent
Problems that can be modeled as filling a limited-size container with a subset of items.
Paths on Grids
Not Frequent
Counting the number of "special" paths on a grid, and how some string problems can be solved using grids.
Longest Increasing Subsequence
Has Not Appeared
Finding and using the longest increasing subsequence of an array.
Bitmask DP
Not Frequent
DP problems that require iterating over subsets.
Updated: Last month
Range DP
Rare
Solving the problem on every contiguous subarray of the original array.
Graphs
Breadth First Search (BFS)
Not Frequent
Traversing a graph in a way such that vertices closer to the starting vertex are processed first.
Disjoint Set Union
Somewhat Frequent
The Disjoint Set Union (DSU) data structure allows you to add edges to an initially empty graph and test whether two vertices of the graph are connected.
Updated: Last month
Topological Sort
Rare
An ordering of vertices in a directed acyclic graph that ensures that a node is visited before every node it has a directed edge to.
Shortest Paths with Non-Negative Edge Weights
Not Frequent
Introduces Bellman-Ford, Floyd-Warshall, Dijkstra.
Updated: Last month
Minimum Spanning Trees
Not Frequent
A subset of the edges of a connected, undirected, edge-weighted graph that connects all the vertices to each other of minimum total weight, where no cycles are allowed.
Data Structures
Trees
Hashing
Rarely required at this level, but still good to know.