Migrate tree-centroid-guess-frontier-cs-algorithmic-54

[ifsheldon]

Issue: migrate Tree Centroid Guess

Handle: tree-centroid-guess-frontier-cs-algorithmic-54
Source: algorithmic/problems/54

Provenance

• Frontier-CS category: algorithmic
• Source path: algorithmic/problems/54
• Source files inspected: config.yaml, statement.txt, interactor.*, and testdata/
• Original execution shape: interactive-style Frontier-CS benchmark

Agentics Migration

• Mode: separated_evaluator
• Target: linux-arm64-cpu
• Solution protocol: zip_project with stdin/stdout
• Evaluator: Python exact-reference checker that writes Agentics result.json
• Public validation: one tiny committed smoke run with answer 0
• Private benchmark: 1 official Frontier-CS-derived run(s) in official-runs.zip

Public/Private Split

Public bundle contains metadata, statement, evaluator code, and tiny validation data only. Official source-derived run records and reference answers are stored in the private overlay at private-benchmark/runs.json plus private answer files.

Acceptance Criteria

• python3 scripts/validate_challenges.py passes in the challenge worktree.
• Public smoke evaluator completes and records a valid Agentics result JSON.
• Private overlay ZIP contains no symlinks or unsafe traversal paths.
• No official private cases or reference answers are committed to Git.

Known Risks

• The original task was interactive; this migration intentionally uses an offline exact-reference stdin/stdout contract, so query-efficiency behavior is not preserved.

[ifsheldon]

Migration lifecycle completed for the temporary MVP publication path.

• Source: algorithmic/problems/54
• PR: Add tree-centroid-guess-frontier-cs-algorithmic-54 #275
• Published challenge: tree-centroid-guess-frontier-cs-algorithmic-54
• Target: linux-arm64-cpu
• Temporary Moltbook URL: https://www.moltbook.com/post/fake-tree-centroid-guess-frontier-cs-algorithmic-54
• Private backup prefix: private-bundle-backups/tree-centroid-guess-frontier-cs-algorithmic-54/
• Smoke submission: def7b403-763c-4530-9299-bc96277e0f88, status completed
• Public observer checks: challenge detail, leaderboard, public submission, public result report, and Moltbook anchor were reachable.

Remaining TODO: replace the fake Moltbook URL with the real post URL.

[ifsheldon]

Resetting this migration back to Todo for a faithful remigration pass.

The previous public bundle and persistent private backup were removed because the execution mode or evaluator contract was materially different from Frontier-CS. The new migration should preserve the original protocol and scoring shape and include a meaningful, non-cheating test solution.

[ifsheldon]

Faithful remigration/reverify complete.

• Source: algorithmic/problems/54
• PR: Remigrate Frontier-CS P1 challenges faithfully #512 merged (c205f3a)
• Production rehearsal: official submission 15c0bd8c-3d00-458e-a477-0b460112620f on linux-arm64-cpu completed with score 0.0
• Observer checks: public challenge detail, submissions list, public result view, leaderboard, and fake Moltbook anchor all verified
• Tracker: Project Add matrix multiplication challenge #1 set to Post-merge; issue Track Frontier-CS non-security problem migrations #9 checklist item checked