| """Request loop run by the grader as uid 65534: python3.11 -I -S -B driver.py PKGROOT. |
| |
| PKGROOT holds a root-owned copy of the *.py files of /app/canary. Each request line is |
| "ID<TAB>PLAN-JSON"; canary.answer(plan) is called with the plan as a dict and the result is |
| written to the original stdout as one line "ID<TAB>OK<TAB>CANON" or "ID<TAB>ERR<TAB>message". |
| CANON is "none" for None and otherwise "q<numerator>/<denominator>", the exact value of the |
| returned number in lowest terms (an int or a fractions.Fraction; floats and bools are refused). |
| Anything the agent's code prints goes to stderr. -S keeps site-packages off sys.path; it is |
| added back explicitly (jinja2). |
| """ |
| import os |
| import sys |
|
|
| proto = os.dup(1) |
| os.dup2(2, 1) |
| sys.path.insert(0, sys.argv[1]) |
| for _p in ("/usr/local/lib/python3.11/site-packages",): |
| sys.path.append(_p) |
| sys.set_int_max_str_digits(0) |
|
|
| import json |
| import numbers |
| from fractions import Fraction |
|
|
|
|
| def answer(text): |
| data = (text.replace("\n", " ").replace("\r", " ") + "\n").encode("utf-8", "replace") |
| while data: |
| n = os.write(proto, data) |
| data = data[n:] |
|
|
|
|
| def canon(v): |
| if v is None: |
| return "none" |
| if isinstance(v, bool) or not isinstance(v, numbers.Rational): |
| raise TypeError("answer must be an int, a Fraction or None, got %s" % type(v).__name__) |
| f = Fraction(v.numerator, v.denominator) |
| return "q%d/%d" % (f.numerator, f.denominator) |
|
|
|
|
| from canary import answer as solve |
|
|
| answer("READY") |
| for line in sys.stdin: |
| line = line.rstrip("\n") |
| if not line: |
| continue |
| rid, payload = line.split("\t", 1) |
| try: |
| plan = json.loads(payload) |
| answer(rid + "\tOK\t" + canon(solve(plan))) |
| except BaseException as exc: |
| answer(rid + "\tERR\t" + ("%s: %s" % (type(exc).__name__, exc))[:300]) |
|
|
