cactus183/patchbench-dev

1from collections import OrderedDict2 3 4class LRUCache:5    def __init__(self, capacity: int):6        if capacity <= 0:7            raise ValueError("capacity must be positive")8        self.capacity = capacity9        self.cache = OrderedDict()10 11    def get(self, key):12        """Get value by key. Returns None if not found."""13        # BUG: does not move key to end (mark as recently used)14        return self.cache.get(key, None)15 16    def put(self, key, value):17        """Insert or update a key-value pair."""18        if key in self.cache:19            self.cache[key] = value20            # BUG: does not move updated key to end21            return22        if len(self.cache) >= self.capacity:23            # Evicts the first item — correct only if access order is maintained24            # But since get() doesn't reorder, this evicts based on insertion order25            self.cache.popitem(last=False)26        self.cache[key] = value27