If your child is serious about competitive programming in China, CSP-J/S is the gateway exam that opens the door to the entire informatics olympiad pathway.
CSP-J/S is the non-professional software ability certification run by the China Computer Federation (CCF), first held in 2019. It is the entry point that strong performers use to qualify for NOIP, provincial selection, and ultimately the National Olympiad in Informatics (NOI). Smart CSP-J/S preparation is less about cramming and more about building genuine algorithmic skill over many months. This guide explains the format, then lays out a realistic study plan.
Understanding the format before you study
Getting the structure right is the first half of preparation. CSP-J/S has two divisions and two rounds, and you cannot reach the second round without clearing the first.
- CSP-J (Junior) is the entry-level division, with gentler algorithmic demands.
- CSP-S (Senior) is the advanced division, expecting deeper data structures and algorithms.
The first round is primarily a written/objective paper: multiple-choice questions on computer science fundamentals, program-reading questions, and program-completion (fill-in-the-blank code) problems. Most students should reason about code on paper, not just at a keyboard. The second round is a timed on-computer programming session where you implement complete solutions and submit source code that is judged on test data. To advance, you must meet your province's first-round cutoff, so do not treat the written round as a formality.
Registration windows, exam dates, score cutoffs, and fees change every year and vary by province. Always confirm current details on the official site before planning. As a rule of thumb, the first round tends to fall in autumn and the second round shortly after, but verify the exact schedule yourself.
Which division should you enter?
Beginners and younger students usually start with CSP-J to build confidence. Students who already command sorting, searching, recursion, and basic dynamic programming can aim directly at CSP-S. There is no strict age restriction, but the exam is designed with school students in mind, and the workload rewards an early start.
A month-by-month preparation plan
Treat CSP-J/S preparation as a multi-month project rather than a sprint. A workable progression looks like this:
- Foundations (months 1-2): Learn C++, the standard language for the exam (the NOI series compiles to a modern C++ standard). Master input/output, arrays, strings, functions, and the STL containers you will lean on constantly.
- Core algorithms (months 2-4): Sorting, binary search, recursion and backtracking, greedy methods, basic graph traversal (BFS/DFS), and introductory dynamic programming.
- Round-one drilling (ongoing): Work through past first-round papers. The program-reading and program-completion sections punish students who only ever run code; practice tracing execution by hand.
- Round-two simulation (final stretch): Solve full problem sets under a strict clock, then read editorials and rewrite weak solutions.
Consistent, deliberate practice on a judged problem set matters more than passive video watching. The skills overlap heavily with international contests, so our overview of USACO is a useful companion read for any informatics student. If you are mapping out a longer competition journey, browse our full competitions hub to see how the pieces connect.
Common mistakes to avoid
- Skipping the written round. Strong coders sometimes fail to advance because they neglected fundamentals and pseudocode tracing.
- Memorizing templates without understanding. Second-round problems are designed to break copy-paste habits.
- Ignoring edge cases and time limits. A correct idea that times out scores poorly; learn to estimate complexity.
- Starting too late. Algorithmic intuition compounds slowly; a few weeks of cramming rarely beats steady terms of practice.
How structured guidance accelerates progress
Self-study works, but a coached pathway shortens the feedback loop: you get problems matched to your level, code reviewed by people who have sat these exams, and a plan that keeps round-one fundamentals and round-two implementation in balance. At BIAA, our competitive programming program is built around exactly this kind of deliberate, level-appropriate practice for K-12 students.
The students who do best in CSP-J/S are not the ones who studied the hardest the month before — they are the ones who started early and practiced consistently.
Ready to build a focused CSP-J/S preparation plan with expert support? Explore BIAA's competitive programming program and take the first concrete step toward the informatics olympiad pathway.