LRU cache

qwen2.5-coder-3b

Pythononeshotrun 2sample 06.2s wall

← run 2 · raw JSON · challenge definitions

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tests (60%)—

deliverables (20%)—

content checks (20%)—

one-shot reply is not valid JSON: Expecting ',' delimiter: line 3 column 17 (char 31)

01 what the model was asked

Create lru.py with a class:

class LRUCache:
    def __init__(self, capacity: int)
    def get(self, key) -> value        # return the stored value, or -1 if absent
    def put(self, key, value) -> None  # insert or update

Semantics: the cache holds at most `capacity` entries. Both get() and put() count as a use of the key. When put() would exceed capacity, evict the least-recently-used key first. put() on an existing key updates its value and makes it most-recently-used.

Use only the Python standard library.

required deliverables + checks

✗deliverable: lru.py

✗lru.py must contain “class LRUCache”

✗lru.py must contain “def get”

✗lru.py must contain “def put”

pytest suite it was graded against

test_lru.py · 46 lines · 842 B

from lru import LRUCache  def test_basic_put_get():    c = LRUCache(2)    c.put("a", 1)    assert c.get("a") == 1    assert c.get("missing") == -1  def test_eviction_order():    c = LRUCache(2)    c.put("a", 1)    c.put("b", 2)    c.put("c", 3)    assert c.get("a") == -1    assert c.get("b") == 2    assert c.get("c") == 3  def test_get_refreshes_recency():    c = LRUCache(2)    c.put("a", 1)    c.put("b", 2)    c.get("a")    c.put("c", 3)    assert c.get("b") == -1    assert c.get("a") == 1  def test_put_overwrite_refreshes():    c = LRUCache(2)    c.put("a", 1)    c.put("b", 2)    c.put("a", 10)    c.put("c", 3)    assert c.get("b") == -1    assert c.get("a") == 10  def test_capacity_one():    c = LRUCache(1)    c.put("a", 1)    c.put("b", 2)    assert c.get("a") == -1    assert c.get("b") == 2

02 what it did — full transcript

promptthe exact instruction sent to the model

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You are completing a coding task in one shot. Write complete files that satisfy the spec below. Tests (pytest) will be run against your files; you cannot run them yourself.

Reply with ONE JSON object and nothing else:
{"files": {"<relative path>": "<complete file content>", ...}}

Required deliverable files: lru.py

SPEC:
Create lru.py with a class:

class LRUCache:
    def __init__(self, capacity: int)
    def get(self, key) -> value        # return the stored value, or -1 if absent
    def put(self, key, value) -> None  # insert or update

Semantics: the cache holds at most `capacity` entries. Both get() and put() count as a use of the key. When put() would exceed capacity, evict the least-recently-used key first. put() on an existing key updates its value and makes it most-recently-used.

Use only the Python standard library.

reply148 tokens

view raw reply

```json
{
  "files": {
    "lru.py": """
from collections import OrderedDict

class LRUCache:
    def __init__(self, capacity: int):
        self.capacity = capacity
        self.cache = OrderedDict()

    def get(self, key) -> int:
        if key in self.cache:
            self.cache.move_to_end(key)
            return self.cache[key]
        else:
            return -1

    def put(self, key, value) -> None:
        if key in self.cache:
            self.cache.move_to_end(key)
        self.cache[key] = value
        if len(self.cache) > self.capacity:
            self.cache.popitem(last=False)
    """
  }
}
```

⚠ degenerate outputone-shot reply is not valid JSON: Expecting ',' delimiter: line 3 column 17 (char 31)

03 what it wrote

The model produced no files.

04 how it was graded

⚠ degenerate —

model calls

invalid actions

self test runs

148

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6.2s

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