Student Coding Tool

Online Compiler

Run quick Java and Python practice programs while working through AP CSA, AP CSP, Python, USACO, data science, and project assignments.

Code editor screen for Java and Python compiler practice

Current language

Java Online Compiler

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Starter idea

Starter idea for Java

public class Main {
    public static void main(String[] args) {
        int[] scores = {88, 92, 79, 95};
        int total = 0;

        for (int score : scores) {
            total += score;
        }

        System.out.println("Average: " + (total / scores.length));
    }
}

If the embedded editor opens with its default sample code, copy this starter into the compiler before running it.

Practice prompts

  • Change the starter data and predict the output before running it.
  • Add one edge case, such as an empty list or a single score.
  • Rewrite the logic using a helper method or function.
  • Explain the bug if the output differs from your prediction.