Getting Started
This is not a heavy course. It is a short orientation for new students: read the language, understand the site format, and recognise common algorithm patterns.
C++ / Python Basics
The input, output, loops, conditions, and arrays used most often on this site.
Learn language basicsHow The Practice Works
Code-block ordering, distractor blocks, fill-in-code, and sample running.
Understand problem typesAlgorithm Pattern Map
Threshold count, two pointers, prefix sums, interval merge, BFS, and DP in plain language.
Open pattern mapAfter the guide, begin with easy problems.
Open Easy problems