problem-package-format 2025-09

[Kevinjil]

• Removed scoring objective; this now always is "maximize".
• Removed scoring keyword from problem.yaml.
• Python 3 is now used for .py files; for backward compatibility .py2 can still be used for Python 2.
• Clarify various things: sample files for interactive problems, testdata.yaml inheritance.
• Updated the CC BY-SA license key to mean version 4.0.
• Allow either a build or run script to be present.
• Change specification of time limit multipliers and allow to explicitly specify a problem time limit.
• Add the problem types multi-pass and submit-answer.
• Add static validators, validators whose input is submission source code.
• Support invalid testdata that validators must fail on.
• Only allow a single output validator, remove validator_flags from problem.yaml, update {input,output}_validator_flags in testdata.yaml.
• Make name required and allow a map from language code to name in that language.
• Add uuid to problem.yaml.
• Add languages to problem.yaml.
• Add support for Markdown problem statements.
• Change languages: and keywords: in problem.yaml to be lists of strings rather than a string of space separated words.
• Clarified when code limit is applied in the case of included code
• Make uuid required in problem.yaml.
• Add /submissions/rejected directory.
• Clarify working directories for submissions and validators.
• Add allow_writing_files to problem.yaml.
• Rename testdata.yaml to test_group.yaml.