From 734973bdac93586ed9601800b503a3a6ad27d202 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Thu, 24 Sep 2026 00:45:16 +0300 Subject: [PATCH 01/16] Update constants.py first task 25.09.2026 --- src/part1/constants.py | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/src/part1/constants.py b/src/part1/constants.py index 9abfbba2..31d4b766 100644 --- a/src/part1/constants.py +++ b/src/part1/constants.py @@ -19,20 +19,20 @@ # Все константы, зависящие от ёмкостей *_BITS, должны вычисляться из них. # Twitter's original Snowflake epoch: 2010-11-04 01:42:54.657 UTC. -EPOCH_MS_DEFAULT: Final[int] = 0 +EPOCH_MS_DEFAULT: Final[int] = 1288834974657 # Node identifier used when the caller does not supply one. -NODE_ID_DEFAULT: Final[int] = 0 +NODE_ID_DEFAULT: Final[int] = 1 # Width of each field, in bits. -TIMESTAMP_BITS: Final[int] = 0 -NODE_ID_BITS: Final[int] = 0 -SEQUENCE_ID_BITS: Final[int] = 0 +TIMESTAMP_BITS: Final[int] = 41 +NODE_ID_BITS: Final[int] = 10 +SEQUENCE_ID_BITS: Final[int] = 12 # Largest value each field can hold. -TIMESTAMP_MS_MAX: Final[int] = 0 -NODE_ID_MAX: Final[int] = 0 -SEQUENCE_ID_MAX: Final[int] = 0 +TIMESTAMP_MS_MAX: Final[int] = 2**41 +NODE_ID_MAX: Final[int] = 2**10 +SEQUENCE_ID_MAX: Final[int] = 2**12 # Здесь можно добавить собственные вспомогательные константы # (например, сдвиги полей при сборке идентификатора). From 8b1ac7b9ba49552b1984fc9770071e2baaecf110 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Thu, 24 Sep 2026 00:45:36 +0300 Subject: [PATCH 02/16] Update snowflake.py first task 25.09.2026 --- src/part1/snowflake.py | 100 +++++++++++------------------------------ 1 file changed, 27 insertions(+), 73 deletions(-) diff --git a/src/part1/snowflake.py b/src/part1/snowflake.py index d3abf050..858d4b0e 100644 --- a/src/part1/snowflake.py +++ b/src/part1/snowflake.py @@ -13,73 +13,37 @@ :func:`decode_node_id` and :func:`decode_sequence_id`. """ -import time # noqa: F401 +import time -from .constants import ( # noqa: F401 +from .constants import ( EPOCH_MS_DEFAULT, + NODE_ID_BITS, NODE_ID_DEFAULT, NODE_ID_MAX, + SEQUENCE_ID_BITS, SEQUENCE_ID_MAX, + TIMESTAMP_BITS, TIMESTAMP_MS_MAX, ) def read_current_millis(epoch_ms: int) -> int: - """Read the number of milliseconds elapsed since the custom epoch. - - Args: - epoch_ms: The custom epoch expressed as Unix milliseconds. - - Returns: - The count of whole milliseconds between ``epoch_ms`` and now. May be - negative if ``epoch_ms`` lies in the future. - """ - # TODO: реализуйте функцию - return 0 + return time.time() - epoch_ms - EPOCH_MS_DEFAULT def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> int: - """Read the timestamp field out of a Snowflake identifier. - - Args: - snowflake_id: An identifier produced against the same epoch. - epoch_ms: The epoch the identifier was generated against. Defaults to - the original Twitter epoch (2010-11-04 01:42:54.657 UTC). - - Returns: - The absolute Unix time in milliseconds at which the identifier was - generated. - """ - # TODO: реализуйте функцию - return 0 + creation_time = (snowflake_id >> SEQUENCE_ID_BITS >> NODE_ID_BITS) & ( + (1 << TIMESTAMP_BITS) - 1 + ) + return creation_time + epoch_ms def decode_node_id(snowflake_id: int) -> int: - """Read the node identifier field out of a Snowflake identifier. - - Args: - snowflake_id: An identifier produced by :func:`generate_snowflake_id`. - - Returns: - The node identifier packed into ``snowflake_id``, in the range - ``[0, NODE_ID_MAX]``. - """ - # TODO: реализуйте функцию - return 0 + return (snowflake_id >> SEQUENCE_ID_BITS) & ((1 << NODE_ID_BITS) - 1) def decode_sequence_id(snowflake_id: int) -> int: - """Read the sequence counter field out of a Snowflake identifier. - - Args: - snowflake_id: An identifier produced by :func:`generate_snowflake_id`. - - Returns: - The per-millisecond sequence counter packed into ``snowflake_id``, in - the range ``[0, SEQUENCE_ID_MAX]``. - """ - # TODO: реализуйте функцию - return 0 + return (snowflake_id) & ((1 << SEQUENCE_ID_BITS) - 1) def generate_snowflake_id( @@ -87,28 +51,18 @@ def generate_snowflake_id( node_id: int = NODE_ID_DEFAULT, epoch_ms: int = EPOCH_MS_DEFAULT, ) -> int | None: - """Build and return a Snowflake identifier for the current millisecond. - - The function is stateless: the caller passes the per-millisecond sequence - counter explicitly. It is the caller's responsibility to increment - ``sequence_id`` for identifiers minted within the same millisecond and to - reset it once the clock advances. - - Args: - sequence_id: The per-millisecond sequence counter, in the range - ``[0, SEQUENCE_ID_MAX]``. - node_id: The identifier of this node, in the range ``[0, NODE_ID_MAX]``. - Optional; defaults to ``NODE_ID_DEFAULT``. - epoch_ms: The start of the epoch as Unix milliseconds. Optional; - defaults to the original Twitter epoch (2010-11-04 01:42:54.657 - UTC). - - Returns: - The Snowflake identifier as a positive 63-bit integer, or ``None`` if - ``node_id`` is outside ``[0, NODE_ID_MAX]``, ``sequence_id`` is outside - ``[0, SEQUENCE_ID_MAX]``, or the elapsed time no longer fits in the - timestamp field (roughly 69 years after ``epoch_ms``). In each of those - cases an explanatory message is printed to stdout first. - """ - # TODO: реализуйте функцию - return 0 + if not (0 <= node_id < NODE_ID_MAX): + print(f"node_id must be in [0, {NODE_ID_MAX}], but it is {node_id}") + return None + if not (0 <= sequence_id < SEQUENCE_ID_MAX): + print(f"sequence_id must be in [0, {SEQUENCE_ID_MAX}], but it is {sequence_id}") + return None + + epoch_ms = time.time() - EPOCH_MS_DEFAULT + if not (0 <= epoch_ms < TIMESTAMP_MS_MAX): + print("overflow") + return None + + return ( + (epoch_ms << NODE_ID_MAX << SEQUENCE_ID_MAX) | (node_id << SEQUENCE_ID_MAX) + ) | sequence_id From 749cadeff3336ca1eb355c222df93f6cfe7eea22 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Thu, 24 Sep 2026 00:55:47 +0300 Subject: [PATCH 03/16] Update snowflake.py update --- src/part1/snowflake.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/part1/snowflake.py b/src/part1/snowflake.py index 858d4b0e..1668befb 100644 --- a/src/part1/snowflake.py +++ b/src/part1/snowflake.py @@ -28,7 +28,7 @@ def read_current_millis(epoch_ms: int) -> int: - return time.time() - epoch_ms - EPOCH_MS_DEFAULT + return int(time.time()) * 1000 - epoch_ms - EPOCH_MS_DEFAULT def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> int: @@ -58,7 +58,7 @@ def generate_snowflake_id( print(f"sequence_id must be in [0, {SEQUENCE_ID_MAX}], but it is {sequence_id}") return None - epoch_ms = time.time() - EPOCH_MS_DEFAULT + epoch_ms = int(time.time()) * 1000 - EPOCH_MS_DEFAULT if not (0 <= epoch_ms < TIMESTAMP_MS_MAX): print("overflow") return None From 97d390d85a809f317a1b7341d56b2b21be9ecef5 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Mon, 28 Sep 2026 23:04:45 +0300 Subject: [PATCH 04/16] Update utils.py Second task utils --- src/part2/utils.py | 27 ++++----------------------- 1 file changed, 4 insertions(+), 23 deletions(-) diff --git a/src/part2/utils.py b/src/part2/utils.py index ec0348d3..1efcd42a 100644 --- a/src/part2/utils.py +++ b/src/part2/utils.py @@ -1,29 +1,10 @@ -"""Standalone helpers shared by the hw4 storage and CRUD modules. - -For now this is limited to money handling: :func:`normalize_price` rounds a -raw :class:`~decimal.Decimal` amount to the fixed number of fractional -digits (:data:`PRICE_PRECISION`) that every stored price uses, keeping -currency values free of binary floating-point error. -""" - -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal from typing import Final -# TODO: задайте число знаков после запятой и шаг квантования -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) def normalize_price(price: Decimal) -> Decimal: - """Round a price to the precision every stored record uses. - - Args: - price: The raw price amount. - - Returns: - ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, - with halves rounded up. - """ - # TODO: реализуйте функцию - return Decimal(0) + return price.quantize(PRICE_STEP, rounding=ROUND_HALF_UP) From 8dc93d5e1f6723be3b070205d51ef2e1f202dd24 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Mon, 28 Sep 2026 23:04:58 +0300 Subject: [PATCH 05/16] Update crud.py second task crud --- src/part2/crud.py | 128 +++++++++++++--------------------------------- 1 file changed, 36 insertions(+), 92 deletions(-) diff --git a/src/part2/crud.py b/src/part2/crud.py index d026cbcb..d221216a 100644 --- a/src/part2/crud.py +++ b/src/part2/crud.py @@ -1,79 +1,39 @@ -"""Create/read/update/delete operations over the in-memory product store. - -Every operation takes the store -- a list of -:data:`~src.part2.storage.Product` tuples -- as its first argument and -works on it in place. The failure path never raises: the operation prints -an explanatory message to stdout and returns ``None``. - -The identifier of a new product is derived from the store itself -(:func:`generate_product_id`): one past the greatest identifier in use, or -:data:`~src.part2.storage.PRODUCT_ID_MIN` when the store is empty. -Product names are kept unique -- :func:`create_product` refuses a name that -is already taken. -""" - from decimal import Decimal -from .storage import ( # noqa: F401 +from .storage import ( NAME_INDEX, PRODUCT_ID_INDEX, PRODUCT_ID_MIN, Product, ) -from .utils import normalize_price # noqa: F401 +from .utils import normalize_price def generate_product_id(storage: list[Product]) -> int: - """Choose the identifier for the next product added to ``storage``. - - Args: - storage: The product store to inspect. - - Returns: - One past the greatest identifier currently held in ``storage``, or - :data:`~src.part2.storage.PRODUCT_ID_MIN` when ``storage`` is - empty. - """ - # TODO: реализуйте функцию - return 0 + if len(storage) == 0: + return PRODUCT_ID_MIN + res = (max(storage, key=lambda prod: prod[PRODUCT_ID_INDEX]))[PRODUCT_ID_INDEX] + 1 + return res def create_product( storage: list[Product], fields: tuple[str, Decimal, int] ) -> int | None: - """Append a new product to ``storage`` and return its new identifier. - - Args: - storage: The product store to append to; modified in place on - success. - fields: A ``(name, price, quantity)`` tuple describing the product. - ``price`` is a :class:`~decimal.Decimal` amount and is rounded - to the stored money precision before it is saved. - - Returns: - The identifier generated for the new product, or ``None`` when a - product with the same name already exists. In the ``None`` case - ``storage`` is left unchanged and a message naming the clashing - name is printed. - """ - # TODO: реализуйте функцию - return 0 + if any(prod[NAME_INDEX] == fields[0] for prod in storage): + print(f"product name {fields[0]} is already taken") + return None + cur_id = generate_product_id(storage) + result: Product = (cur_id, fields[0], normalize_price(fields[1]), fields[2]) + storage.append(result) + return cur_id def read_product(storage: list[Product], product_id: int) -> Product | None: - """Return the product stored under ``product_id``. - - Args: - storage: The product store to search. - product_id: The identifier to look up. - - Returns: - The matching ``(product_id, name, price, quantity)`` record, or - ``None`` when no product carries that identifier (a message is - printed in that case). - """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for prod in storage: + if prod[PRODUCT_ID_INDEX] == product_id: + return prod + print(f"no product with id {product_id}") + return None def update_product( @@ -81,40 +41,24 @@ def update_product( product_id: int, fields: tuple[str, Decimal, int], ) -> Product | None: - """Overwrite the fields of the product stored under ``product_id``. - - The identifier itself is preserved; only ``name``, ``price`` and - ``quantity`` are replaced. - - Args: - storage: The product store to modify; the matching record is - replaced in place on success. - product_id: The identifier of the product to change. - fields: A ``(name, price, quantity)`` tuple with the new values. - ``price`` is a :class:`~decimal.Decimal` amount and is rounded - to the stored money precision before it is saved. - - Returns: - The updated ``(product_id, name, price, quantity)`` record, or - ``None`` when no product carries that identifier (``storage`` is - left unchanged and a message is printed). - """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + new_product: Product = ( + product_id, + fields[0], + normalize_price(fields[1]), + fields[2], + ) + storage[ind] = new_product + return storage[ind] + print(f"no product with id {product_id}") + return None def delete_product(storage: list[Product], product_id: int) -> int | None: - """Remove the product stored under ``product_id`` from ``storage``. - - Args: - storage: The product store to remove from; modified in place on - success. - product_id: The identifier of the product to remove. - - Returns: - ``product_id`` when a product was removed, or ``None`` when no - product carried that identifier (``storage`` is left unchanged and - a message is printed). - """ - # TODO: реализуйте функцию - return 0 + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + del storage[ind] + return product_id + print(f"no product with id {product_id}") + return None From f9153b3b59dec0758fba40c0d4d6a229b0a13d88 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Mon, 28 Sep 2026 23:05:21 +0300 Subject: [PATCH 06/16] Update storage.py second task storage --- src/part2/storage.py | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/part2/storage.py b/src/part2/storage.py index b63d5fc7..35821c5f 100644 --- a/src/part2/storage.py +++ b/src/part2/storage.py @@ -26,9 +26,9 @@ # TODO: задайте позиции полей внутри кортежа Product PRODUCT_ID_INDEX: Final = 0 -NAME_INDEX: Final = 0 -PRICE_INDEX: Final = 0 -QUANTITY_INDEX: Final = 0 +NAME_INDEX: Final = 1 +PRICE_INDEX: Final = 2 +QUANTITY_INDEX: Final = 3 # TODO: задайте идентификатор первого товара в пустом хранилище -PRODUCT_ID_MIN: Final[int] = 0 +PRODUCT_ID_MIN: Final[int] = 1 From fddb8de39f1fe2675b932cafc1e956a6c92f2fe0 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Mon, 28 Sep 2026 23:05:34 +0300 Subject: [PATCH 07/16] Update cart.py second task cart --- src/part2/cart.py | 133 +++++++++++++++++++++++++--------------------- 1 file changed, 72 insertions(+), 61 deletions(-) diff --git a/src/part2/cart.py b/src/part2/cart.py index 063f9aea..ca4859e1 100644 --- a/src/part2/cart.py +++ b/src/part2/cart.py @@ -1,18 +1,7 @@ -"""Shopping-cart operations layered on top of the product store. - -The cart is a plain list of tuples, one :data:`CartLine` -- -``(product_id, quantity)`` -- per distinct product. Moving units between the -store and the cart keeps the two sides in balance: :func:`add_to_cart` takes -units out of stock, :func:`remove_from_cart` puts them back. - -Like the CRUD layer, the failure path never raises -- the operation prints -an explanatory message to stdout and returns ``None``. -""" - from typing import Final -from .crud import read_product, update_product # noqa: F401 -from .storage import ( # noqa: F401 +from .crud import read_product, update_product +from .storage import ( NAME_INDEX, PRICE_INDEX, QUANTITY_INDEX, @@ -22,9 +11,34 @@ type CartLine = tuple[int, int] -# TODO: задайте позиции полей внутри кортежа CartLine + LINE_PRODUCT_ID_INDEX: Final = 0 -LINE_QUANTITY_INDEX: Final = 0 +LINE_QUANTITY_INDEX: Final = 1 + + +def find_cart_line(cart: list[CartLine], product_id: int) -> CartLine | None: + for c_prod in cart: + if c_prod[LINE_PRODUCT_ID_INDEX] == product_id: + return c_prod + print(f"no product with id {product_id} in the cart") + return None + + +def change_cart_quantity( + cart: list[CartLine], + product_id: int, + quantity: int, +) -> int | None: + for ind in range(len(cart)): + if cart[ind][LINE_PRODUCT_ID_INDEX] == product_id: + new_c_prod: CartLine = ( + product_id, + cart[ind][LINE_QUANTITY_INDEX] - quantity, + ) + cart[ind] = new_c_prod + return ind + print(f"no product with id {product_id} in cart") + return None def add_to_cart( @@ -33,28 +47,25 @@ def add_to_cart( product_id: int, quantity: int, ) -> CartLine | None: - """Move ``quantity`` units of ``product_id`` from the store into ``cart``. - - The product is looked up in ``storage``. If it is missing, a message is - printed (by :func:`~src.part2.crud.read_product`) and nothing - changes. If the store holds fewer units than requested, an explanatory - message is printed and nothing changes. Otherwise the store record is - decremented by ``quantity`` and the cart line for ``product_id`` gains - ``quantity`` units -- a new line is created when the cart had none. - - Args: - storage: The product store to draw stock from; modified in place on - success. - cart: The cart to add the units to; modified in place on success. - product_id: The identifier of the product to add. - quantity: Number of units to move into the cart. - - Returns: - The cart line for ``product_id`` after the addition, or ``None`` - when the product is unknown or the store cannot cover the request. - """ - # TODO: реализуйте функцию - return (0, 0) + prod = read_product(storage, product_id) + if prod is None: + return None + if prod[QUANTITY_INDEX] < quantity: + print( + f"not enough stock for product {product_id}: {prod[QUANTITY_INDEX]} available, {quantity} requested" + ) + return None + update_product( + storage, + product_id, + (prod[NAME_INDEX], prod[PRICE_INDEX], prod[QUANTITY_INDEX] - quantity), + ) + for ind in range(len(cart)): + if cart[ind][LINE_PRODUCT_ID_INDEX] == product_id: + cart[ind] = (product_id, cart[ind][LINE_QUANTITY_INDEX] + quantity) + return cart[ind] + cart.append((product_id, quantity)) + return cart[-1] def remove_from_cart( @@ -63,27 +74,27 @@ def remove_from_cart( product_id: int, quantity: int, ) -> CartLine | None: - """Move ``quantity`` units of ``product_id`` from ``cart`` back to the store. - - The cart line for ``product_id`` is looked up. If there is none, a - message is printed and nothing changes. If the line holds fewer units - than requested, an explanatory message is printed and nothing changes. - Otherwise the cart line loses ``quantity`` units -- the line is dropped - when it reaches zero -- and the store record gains ``quantity`` units - back. - - Args: - storage: The product store to return stock to; modified in place on - success. - cart: The cart to take the units from; modified in place on - success. - product_id: The identifier of the product to remove. - quantity: Number of units to move back into the store. - - Returns: - The cart line for ``product_id`` after the removal (a quantity of - zero means the line was dropped), or ``None`` when the cart has no - line for the product or holds too few units. - """ - # TODO: реализуйте функцию - return (0, 0) + c_prod = find_cart_line(cart, product_id) + if c_prod is None: + return None + if c_prod[LINE_QUANTITY_INDEX] < quantity: + print( + f"cart holds only {c_prod[LINE_QUANTITY_INDEX]} unit(s) of product {product_id}, cannot remove {quantity}" + ) + return None + prod = read_product(storage, product_id) + if prod is None: + return None + update_product( + storage, + product_id, + (prod[NAME_INDEX], prod[PRICE_INDEX], prod[QUANTITY_INDEX] + quantity), + ) + ind = change_cart_quantity(cart, product_id, quantity) + if ind is None: + return None + if cart[ind][LINE_QUANTITY_INDEX] == 0: + res = cart[ind] + del cart[ind] + return res + return cart[ind] From f9f21177295f22be89858dc3194de4fd4b95a3ec Mon Sep 17 00:00:00 2001 From: Lena Date: Fri, 9 Oct 2026 20:50:09 +0300 Subject: [PATCH 08/16] Update storage.py --- src/part2/storage.py | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/part2/storage.py b/src/part2/storage.py index b63d5fc7..35821c5f 100644 --- a/src/part2/storage.py +++ b/src/part2/storage.py @@ -26,9 +26,9 @@ # TODO: задайте позиции полей внутри кортежа Product PRODUCT_ID_INDEX: Final = 0 -NAME_INDEX: Final = 0 -PRICE_INDEX: Final = 0 -QUANTITY_INDEX: Final = 0 +NAME_INDEX: Final = 1 +PRICE_INDEX: Final = 2 +QUANTITY_INDEX: Final = 3 # TODO: задайте идентификатор первого товара в пустом хранилище -PRODUCT_ID_MIN: Final[int] = 0 +PRODUCT_ID_MIN: Final[int] = 1 From 2bb974763d652841541a37f2b6412a47b210c06e Mon Sep 17 00:00:00 2001 From: Lena Date: Fri, 9 Oct 2026 20:50:38 +0300 Subject: [PATCH 09/16] Update utils.py --- src/part2/utils.py | 27 ++++----------------------- 1 file changed, 4 insertions(+), 23 deletions(-) diff --git a/src/part2/utils.py b/src/part2/utils.py index 11bd7a76..1efcd42a 100644 --- a/src/part2/utils.py +++ b/src/part2/utils.py @@ -1,29 +1,10 @@ -"""Standalone helpers shared by the part2 storage and CRUD modules. - -For now this is limited to money handling: :func:`normalize_price` rounds a -raw :class:`~decimal.Decimal` amount to the fixed number of fractional -digits (:data:`PRICE_PRECISION`) that every stored price uses, keeping -currency values free of binary floating-point error. -""" - -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal from typing import Final -# TODO: задайте число знаков после запятой и шаг квантования -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) def normalize_price(price: Decimal) -> Decimal: - """Round a price to the precision every stored record uses. - - Args: - price: The raw price amount. - - Returns: - ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, - with halves rounded up. - """ - # TODO: реализуйте функцию - return Decimal(0) + return price.quantize(PRICE_STEP, rounding=ROUND_HALF_UP) From 658658819eb7b28ee18f7b0f74f364a7ef936271 Mon Sep 17 00:00:00 2001 From: Lena Date: Fri, 9 Oct 2026 20:51:06 +0300 Subject: [PATCH 10/16] Update crud.py --- src/part2/crud.py | 128 +++++++++++++--------------------------------- 1 file changed, 36 insertions(+), 92 deletions(-) diff --git a/src/part2/crud.py b/src/part2/crud.py index d026cbcb..d221216a 100644 --- a/src/part2/crud.py +++ b/src/part2/crud.py @@ -1,79 +1,39 @@ -"""Create/read/update/delete operations over the in-memory product store. - -Every operation takes the store -- a list of -:data:`~src.part2.storage.Product` tuples -- as its first argument and -works on it in place. The failure path never raises: the operation prints -an explanatory message to stdout and returns ``None``. - -The identifier of a new product is derived from the store itself -(:func:`generate_product_id`): one past the greatest identifier in use, or -:data:`~src.part2.storage.PRODUCT_ID_MIN` when the store is empty. -Product names are kept unique -- :func:`create_product` refuses a name that -is already taken. -""" - from decimal import Decimal -from .storage import ( # noqa: F401 +from .storage import ( NAME_INDEX, PRODUCT_ID_INDEX, PRODUCT_ID_MIN, Product, ) -from .utils import normalize_price # noqa: F401 +from .utils import normalize_price def generate_product_id(storage: list[Product]) -> int: - """Choose the identifier for the next product added to ``storage``. - - Args: - storage: The product store to inspect. - - Returns: - One past the greatest identifier currently held in ``storage``, or - :data:`~src.part2.storage.PRODUCT_ID_MIN` when ``storage`` is - empty. - """ - # TODO: реализуйте функцию - return 0 + if len(storage) == 0: + return PRODUCT_ID_MIN + res = (max(storage, key=lambda prod: prod[PRODUCT_ID_INDEX]))[PRODUCT_ID_INDEX] + 1 + return res def create_product( storage: list[Product], fields: tuple[str, Decimal, int] ) -> int | None: - """Append a new product to ``storage`` and return its new identifier. - - Args: - storage: The product store to append to; modified in place on - success. - fields: A ``(name, price, quantity)`` tuple describing the product. - ``price`` is a :class:`~decimal.Decimal` amount and is rounded - to the stored money precision before it is saved. - - Returns: - The identifier generated for the new product, or ``None`` when a - product with the same name already exists. In the ``None`` case - ``storage`` is left unchanged and a message naming the clashing - name is printed. - """ - # TODO: реализуйте функцию - return 0 + if any(prod[NAME_INDEX] == fields[0] for prod in storage): + print(f"product name {fields[0]} is already taken") + return None + cur_id = generate_product_id(storage) + result: Product = (cur_id, fields[0], normalize_price(fields[1]), fields[2]) + storage.append(result) + return cur_id def read_product(storage: list[Product], product_id: int) -> Product | None: - """Return the product stored under ``product_id``. - - Args: - storage: The product store to search. - product_id: The identifier to look up. - - Returns: - The matching ``(product_id, name, price, quantity)`` record, or - ``None`` when no product carries that identifier (a message is - printed in that case). - """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for prod in storage: + if prod[PRODUCT_ID_INDEX] == product_id: + return prod + print(f"no product with id {product_id}") + return None def update_product( @@ -81,40 +41,24 @@ def update_product( product_id: int, fields: tuple[str, Decimal, int], ) -> Product | None: - """Overwrite the fields of the product stored under ``product_id``. - - The identifier itself is preserved; only ``name``, ``price`` and - ``quantity`` are replaced. - - Args: - storage: The product store to modify; the matching record is - replaced in place on success. - product_id: The identifier of the product to change. - fields: A ``(name, price, quantity)`` tuple with the new values. - ``price`` is a :class:`~decimal.Decimal` amount and is rounded - to the stored money precision before it is saved. - - Returns: - The updated ``(product_id, name, price, quantity)`` record, or - ``None`` when no product carries that identifier (``storage`` is - left unchanged and a message is printed). - """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + new_product: Product = ( + product_id, + fields[0], + normalize_price(fields[1]), + fields[2], + ) + storage[ind] = new_product + return storage[ind] + print(f"no product with id {product_id}") + return None def delete_product(storage: list[Product], product_id: int) -> int | None: - """Remove the product stored under ``product_id`` from ``storage``. - - Args: - storage: The product store to remove from; modified in place on - success. - product_id: The identifier of the product to remove. - - Returns: - ``product_id`` when a product was removed, or ``None`` when no - product carried that identifier (``storage`` is left unchanged and - a message is printed). - """ - # TODO: реализуйте функцию - return 0 + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + del storage[ind] + return product_id + print(f"no product with id {product_id}") + return None From 8f90ead163d94addfeac58a93465e99efc9c2efe Mon Sep 17 00:00:00 2001 From: Lena Date: Fri, 9 Oct 2026 20:51:26 +0300 Subject: [PATCH 11/16] Update cart.py --- src/part2/cart.py | 133 +++++++++++++++++++++++++--------------------- 1 file changed, 72 insertions(+), 61 deletions(-) diff --git a/src/part2/cart.py b/src/part2/cart.py index 063f9aea..ca4859e1 100644 --- a/src/part2/cart.py +++ b/src/part2/cart.py @@ -1,18 +1,7 @@ -"""Shopping-cart operations layered on top of the product store. - -The cart is a plain list of tuples, one :data:`CartLine` -- -``(product_id, quantity)`` -- per distinct product. Moving units between the -store and the cart keeps the two sides in balance: :func:`add_to_cart` takes -units out of stock, :func:`remove_from_cart` puts them back. - -Like the CRUD layer, the failure path never raises -- the operation prints -an explanatory message to stdout and returns ``None``. -""" - from typing import Final -from .crud import read_product, update_product # noqa: F401 -from .storage import ( # noqa: F401 +from .crud import read_product, update_product +from .storage import ( NAME_INDEX, PRICE_INDEX, QUANTITY_INDEX, @@ -22,9 +11,34 @@ type CartLine = tuple[int, int] -# TODO: задайте позиции полей внутри кортежа CartLine + LINE_PRODUCT_ID_INDEX: Final = 0 -LINE_QUANTITY_INDEX: Final = 0 +LINE_QUANTITY_INDEX: Final = 1 + + +def find_cart_line(cart: list[CartLine], product_id: int) -> CartLine | None: + for c_prod in cart: + if c_prod[LINE_PRODUCT_ID_INDEX] == product_id: + return c_prod + print(f"no product with id {product_id} in the cart") + return None + + +def change_cart_quantity( + cart: list[CartLine], + product_id: int, + quantity: int, +) -> int | None: + for ind in range(len(cart)): + if cart[ind][LINE_PRODUCT_ID_INDEX] == product_id: + new_c_prod: CartLine = ( + product_id, + cart[ind][LINE_QUANTITY_INDEX] - quantity, + ) + cart[ind] = new_c_prod + return ind + print(f"no product with id {product_id} in cart") + return None def add_to_cart( @@ -33,28 +47,25 @@ def add_to_cart( product_id: int, quantity: int, ) -> CartLine | None: - """Move ``quantity`` units of ``product_id`` from the store into ``cart``. - - The product is looked up in ``storage``. If it is missing, a message is - printed (by :func:`~src.part2.crud.read_product`) and nothing - changes. If the store holds fewer units than requested, an explanatory - message is printed and nothing changes. Otherwise the store record is - decremented by ``quantity`` and the cart line for ``product_id`` gains - ``quantity`` units -- a new line is created when the cart had none. - - Args: - storage: The product store to draw stock from; modified in place on - success. - cart: The cart to add the units to; modified in place on success. - product_id: The identifier of the product to add. - quantity: Number of units to move into the cart. - - Returns: - The cart line for ``product_id`` after the addition, or ``None`` - when the product is unknown or the store cannot cover the request. - """ - # TODO: реализуйте функцию - return (0, 0) + prod = read_product(storage, product_id) + if prod is None: + return None + if prod[QUANTITY_INDEX] < quantity: + print( + f"not enough stock for product {product_id}: {prod[QUANTITY_INDEX]} available, {quantity} requested" + ) + return None + update_product( + storage, + product_id, + (prod[NAME_INDEX], prod[PRICE_INDEX], prod[QUANTITY_INDEX] - quantity), + ) + for ind in range(len(cart)): + if cart[ind][LINE_PRODUCT_ID_INDEX] == product_id: + cart[ind] = (product_id, cart[ind][LINE_QUANTITY_INDEX] + quantity) + return cart[ind] + cart.append((product_id, quantity)) + return cart[-1] def remove_from_cart( @@ -63,27 +74,27 @@ def remove_from_cart( product_id: int, quantity: int, ) -> CartLine | None: - """Move ``quantity`` units of ``product_id`` from ``cart`` back to the store. - - The cart line for ``product_id`` is looked up. If there is none, a - message is printed and nothing changes. If the line holds fewer units - than requested, an explanatory message is printed and nothing changes. - Otherwise the cart line loses ``quantity`` units -- the line is dropped - when it reaches zero -- and the store record gains ``quantity`` units - back. - - Args: - storage: The product store to return stock to; modified in place on - success. - cart: The cart to take the units from; modified in place on - success. - product_id: The identifier of the product to remove. - quantity: Number of units to move back into the store. - - Returns: - The cart line for ``product_id`` after the removal (a quantity of - zero means the line was dropped), or ``None`` when the cart has no - line for the product or holds too few units. - """ - # TODO: реализуйте функцию - return (0, 0) + c_prod = find_cart_line(cart, product_id) + if c_prod is None: + return None + if c_prod[LINE_QUANTITY_INDEX] < quantity: + print( + f"cart holds only {c_prod[LINE_QUANTITY_INDEX]} unit(s) of product {product_id}, cannot remove {quantity}" + ) + return None + prod = read_product(storage, product_id) + if prod is None: + return None + update_product( + storage, + product_id, + (prod[NAME_INDEX], prod[PRICE_INDEX], prod[QUANTITY_INDEX] + quantity), + ) + ind = change_cart_quantity(cart, product_id, quantity) + if ind is None: + return None + if cart[ind][LINE_QUANTITY_INDEX] == 0: + res = cart[ind] + del cart[ind] + return res + return cart[ind] From 319c9b5ef320db6037da0c96247f7ad50b25a919 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Fri, 9 Oct 2026 22:52:36 +0300 Subject: [PATCH 12/16] Update crud.py --- src/part3/crud.py | 150 +++++++++++++++------------------------------- 1 file changed, 47 insertions(+), 103 deletions(-) diff --git a/src/part3/crud.py b/src/part3/crud.py index 68811d7e..d2e0179d 100644 --- a/src/part3/crud.py +++ b/src/part3/crud.py @@ -1,87 +1,43 @@ -"""Create/read/update/delete operations over the in-memory product store. - -Every operation takes the store -- a list of -:data:`~src.part3.storage.Product` tuples -- as its first argument and -works on it in place. The failure path never raises: the operation prints -an explanatory message to stdout and returns ``None``. - -The identifier of a new product is derived from the store itself -(:func:`generate_product_id`): one past the greatest identifier in use, or -:data:`~src.part3.storage.PRODUCT_ID_MIN` when the store is empty. - -Every product name that reaches the store is passed through -:func:`~src.part3.utils.normalize_product_name` first. A name that -normalises to an empty string is rejected -- the operation prints a -message and changes nothing. Names are also kept unique -- -:func:`create_product` refuses a normalised name that is already taken, -and :func:`update_product` refuses one that is already taken by another -product. -""" - from decimal import Decimal -from .storage import ( # noqa: F401 +from .storage import ( NAME_INDEX, PRODUCT_ID_INDEX, PRODUCT_ID_MIN, Product, ) -from .utils import normalize_price, normalize_product_name # noqa: F401 +from .utils import normalize_price, normalize_product_name def generate_product_id(storage: list[Product]) -> int: - """Choose the identifier for the next product added to ``storage``. - - Args: - storage: The product store to inspect. - - Returns: - One past the greatest identifier currently held in ``storage``, or - :data:`~src.part3.storage.PRODUCT_ID_MIN` when ``storage`` is - empty. - """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return 0 + if len(storage) == 0: + return PRODUCT_ID_MIN + res = (max(storage, key=lambda prod: prod[PRODUCT_ID_INDEX]))[PRODUCT_ID_INDEX] + 1 + return res def create_product( storage: list[Product], fields: tuple[str, Decimal, int] ) -> int | None: - """Append a new product to ``storage`` and return its new identifier. - - Args: - storage: The product store to append to; modified in place on - success. - fields: A ``(name, price, quantity)`` tuple describing the product. - ``name`` is normalised (surrounding whitespace stripped, - lower-cased) before it is stored or compared. ``price`` is a - :class:`~decimal.Decimal` amount and is rounded to the stored - money precision before it is saved. - - Returns: - The identifier generated for the new product, or ``None`` when - ``name`` is blank once normalised or a product with the same - normalised name already exists. In the ``None`` case ``storage`` - is left unchanged and an explanatory message is printed. - """ - # TODO: реализуйте функцию - return 0 + name = normalize_product_name(fields[0]) + if not name: + print("product name must not be blank") + return None + if any(prod[NAME_INDEX] == name for prod in storage): + print(f"product name {name} is already taken") + return None + cur_id = generate_product_id(storage) + result: Product = (cur_id, name, normalize_price(fields[1]), fields[2]) + storage.append(result) + return cur_id def read_product(storage: list[Product], product_id: int) -> Product | None: - """Return the product stored under ``product_id``. - - Args: - storage: The product store to search. - product_id: The identifier to look up. - - Returns: - The matching ``(product_id, name, price, quantity)`` record, or - ``None`` when no product carries that identifier (a message is - printed in that case). - """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return (0, "", Decimal(0), 0) + for prod in storage: + if prod[PRODUCT_ID_INDEX] == product_id: + return prod + print(f"no product with id {product_id}") + return None def update_product( @@ -89,43 +45,31 @@ def update_product( product_id: int, fields: tuple[str, Decimal, int], ) -> Product | None: - """Overwrite the fields of the product stored under ``product_id``. - - The identifier itself is preserved; only ``name``, ``price`` and - ``quantity`` are replaced. - - Args: - storage: The product store to modify; the matching record is - replaced in place on success. - product_id: The identifier of the product to change. - fields: A ``(name, price, quantity)`` tuple with the new values. - ``price`` is a :class:`~decimal.Decimal` amount and is rounded - to the stored money precision before it is saved. - - Returns: - The updated ``(product_id, name, price, quantity)`` record, or - ``None`` when ``name`` is blank once normalised, no product - carries that identifier, or the normalised name is already taken - by another product. In every ``None`` case ``storage`` is left - unchanged and an explanatory message is printed. Renaming a - product to its own current name is allowed. - """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + name = normalize_product_name(fields[0]) + if not name: + print("product name must not be blank") + return None + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + new_product: Product = ( + product_id, + name, + normalize_price(fields[1]), + fields[2], + ) + storage[ind] = new_product + return storage[ind] + if storage[ind][NAME_INDEX] == name: + print(f"product name {name} is already taken") + return None + print(f"no product with id {product_id}") + return None def delete_product(storage: list[Product], product_id: int) -> int | None: - """Remove the product stored under ``product_id`` from ``storage``. - - Args: - storage: The product store to remove from; modified in place on - success. - product_id: The identifier of the product to remove. - - Returns: - ``product_id`` when a product was removed, or ``None`` when no - product carried that identifier (``storage`` is left unchanged and - a message is printed). - """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return 0 + for ind in range(len(storage)): + if storage[ind][PRODUCT_ID_INDEX] == product_id: + del storage[ind] + return product_id + print(f"no product with id {product_id}") + return None From d3d7c8166834e3cb4138affb23856c9aead68026 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Fri, 9 Oct 2026 22:52:44 +0300 Subject: [PATCH 13/16] Update run_admin.py --- src/part3/run_admin.py | 144 ++++++++++++++++++----------------------- 1 file changed, 63 insertions(+), 81 deletions(-) diff --git a/src/part3/run_admin.py b/src/part3/run_admin.py index c5feeb0b..51d36446 100644 --- a/src/part3/run_admin.py +++ b/src/part3/run_admin.py @@ -1,107 +1,89 @@ -"""Interactive admin console for the part3 in-memory product store. - -Running this module starts a read-eval-print loop over a single product -store that lives in memory for the lifetime of the process. Every line -typed at the prompt is stripped of surrounding whitespace and matched -against the set of known commands: - -* ``help`` -- print the list of commands and what each one does; -* ``exit`` -- leave the loop and end the program; -* ``show`` -- print the whole store as a text table; -* ``create `` -- add a product; -* ``read `` -- print one product; -* ``update `` -- overwrite a product; -* ``delete `` -- remove a product. - -For ``create`` and ``update`` the price and quantity are always the last -two words of the line; everything between the verb (and, for ``update``, -the id) and those two words is joined with single spaces into the -product name, so a multi-word name such as ``Gibson SG Junior`` needs no -quoting. - -The four CRUD commands forward to :mod:`src.part3.crud`; whatever -that call returns is printed unless it is ``None``. A line whose first -word is not a known verb, or that carries the wrong number of arguments -for its verb, prints an "is not a command" notice. A line that names a -command correctly but whose id, price or quantity argument will not -parse prints a distinct "arguments are invalid" notice. Either way the -store is left untouched and the loop keeps running; only ``exit`` stops -it. -""" - -from decimal import Decimal, InvalidOperation # noqa: F401 +from decimal import Decimal, InvalidOperation from typing import Final -from .crud import ( # noqa: F401 +from .crud import ( create_product, delete_product, read_product, update_product, ) from .storage import Product -from .utils import get_storage_str_representation # noqa: F401 +from .utils import get_storage_str_representation -# TODO: задайте приглашение и текст справки -PROMPT: Final[str] = "" -HELP_TEXT: Final[str] = "" +PROMPT: Final[str] = "admin>" +HELP_TEXT: Final[str] = """ + Available commands: + help show this message + exit leave the console + show print the whole store as a table + create add a product, print its new id + read print the product with that id + update overwrite that product's fields + delete remove the product with that id +For create and update the price and quantity are the last two words of the line; +everything before them is the product name, so it may contain spaces +(for example "Gibson SG Junior") and needs no quoting.""" -def show_help() -> None: - """Print the command reference to stdout. - The text is the module-level :data:`HELP_TEXT` constant, printed as - is: a heading, one line per command with a short description, and a - note on how multi-word names are parsed. - """ - # TODO: реализуйте функцию +def show_help() -> None: + print(HELP_TEXT) def print_result(result: object) -> None: - """Print a CRUD result to stdout unless it is ``None``. - - Args: - result: The value returned by a CRUD operation. ``None`` means the - operation already reported its own failure, so nothing is - printed in that case. - """ - # TODO: реализуйте функцию + if result: + print(result) def run_command(storage: list[Product], line: str) -> bool: - """Parse one console line and carry out the command it names. - - Args: - storage: The product store shared across the session; mutated in - place by the ``create``, ``update`` and ``delete`` commands. - line: One line of console input, already stripped of surrounding - whitespace. - - Returns: - ``True`` to keep the read-eval-print loop running, or ``False`` - once the ``exit`` command has been seen. A line that is not a - known command prints a notice and still returns ``True``. - - Raises: - ValueError: If an id or quantity argument of a CRUD command does - not parse as a base-10 integer. - decimal.InvalidOperation: If the price argument of ``create`` or - ``update`` does not parse as a decimal number. - """ - # TODO: реализуйте функцию + command = line.split() + match command: + case ["help"]: + show_help() + return True + case ["exit"]: + return False + case ["show"]: + print(get_storage_str_representation(storage)) + return True + case ["create", name, s_price, s_quantity]: + price = Decimal(s_price) + quantity = int(s_quantity) + fields = (name, price, quantity) + res = create_product(storage, fields) + if res: + print(res) + return True + case ["read", s_product_id]: + product_id = int(s_product_id) + res_r = read_product(storage, product_id) + if res_r: + print(res_r) + return True + case ["update", s_product_id, name, s_price, s_quantity]: + product_id = int(s_product_id) + price = Decimal(s_price) + quantity = int(s_quantity) + fields = (name, price, quantity) + res_u = update_product(storage, product_id, fields) + if res_u: + print(res_u) + return True + case ["delete", s_product_id]: + product_id = int(s_product_id) + res_d = delete_product(storage, product_id) + if res_d: + print(res_d) + return True + case [_]: + print(f"{line} is not a command") + return True return False def main() -> None: - """Run the admin console until the ``exit`` command is entered. - - A single product store is created empty and kept in memory for the - whole session. Each iteration reads one line from stdin, strips its - surrounding whitespace and hands it to :func:`run_command`. A line - that names a command but whose id, price or quantity argument does - not parse is caught here and reported without stopping the loop; only - ``exit`` ends it. - """ + storage: list[Product] = [] running = True From f1320aee73f2debd33730536935ab392cc09b7d9 Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Fri, 9 Oct 2026 22:52:49 +0300 Subject: [PATCH 14/16] Update storage.py --- src/part3/storage.py | 31 +++++-------------------------- 1 file changed, 5 insertions(+), 26 deletions(-) diff --git a/src/part3/storage.py b/src/part3/storage.py index c5e34be5..9cbec756 100644 --- a/src/part3/storage.py +++ b/src/part3/storage.py @@ -1,35 +1,14 @@ -"""In-memory product store for the shop CRUD exercise. - -The store is deliberately primitive: a plain list of tuples, with no -persistence, no indexing and no schema enforcement. Each element is a -:data:`Product` record -- a ``(product_id, name, price, quantity)`` tuple -where: - -* ``product_id`` -- unique positive integer key, assigned by the create - operation in :mod:`src.part3.crud`; -* ``name`` -- human-readable product name, unique across the store; -* ``price`` -- price of a single unit, held as a :class:`~decimal.Decimal` - amount rounded to a fixed number of decimal places (see - :func:`src.part3.utils.normalize_price`) so that money is never - subject to binary floating-point error; -* ``quantity`` -- number of units currently in stock. - -Field positions are exposed as ``*_INDEX`` constants so callers never -hard-code tuple offsets. -""" - from decimal import Decimal from typing import Final type Product = tuple[int, str, Decimal, int] -# TODO: задайте позиции полей внутри кортежа Product (используйте своё решение -# части 2) +# TODO: задайте позиции полей внутри кортежа Product PRODUCT_ID_INDEX: Final = 0 -NAME_INDEX: Final = 0 -PRICE_INDEX: Final = 0 -QUANTITY_INDEX: Final = 0 +NAME_INDEX: Final = 1 +PRICE_INDEX: Final = 2 +QUANTITY_INDEX: Final = 3 # TODO: задайте идентификатор первого товара в пустом хранилище -PRODUCT_ID_MIN: Final[int] = 0 +PRODUCT_ID_MIN: Final[int] = 1 From 9009f6817cba541e2979f7a09ec25c1a9a145c2f Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Fri, 9 Oct 2026 22:52:52 +0300 Subject: [PATCH 15/16] Update utils.py --- src/part3/utils.py | 124 +++++++++++++++++---------------------------- 1 file changed, 46 insertions(+), 78 deletions(-) diff --git a/src/part3/utils.py b/src/part3/utils.py index 318ded0b..f2222e99 100644 --- a/src/part3/utils.py +++ b/src/part3/utils.py @@ -1,95 +1,63 @@ -"""Standalone helpers shared by the part3 storage and CRUD modules. - -Normalisation: - -* :func:`normalize_price` rounds a raw :class:`~decimal.Decimal` amount to - the fixed number of fractional digits (:data:`PRICE_PRECISION`) that - every stored price uses, keeping currency values free of binary - floating-point error. -* :func:`normalize_product_name` strips surrounding whitespace from a - product name, collapses every internal run of whitespace to a single - space and lower-cases it, giving every stored name a single canonical - form. - -Presentation: - -* :func:`get_storage_str_representation` renders the whole store as a - text table meant to be printed to a terminal; each column is sized to - the longest value it holds in that particular call. -""" - -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal from typing import Final -from .storage import Product - +from .storage import ( + NAME_INDEX, + PRICE_INDEX, + PRODUCT_ID_INDEX, + QUANTITY_INDEX, + Product, +) -# Number of fractional digits every stored price is rounded to. -# Quantisation step derived from PRICE_PRECISION, e.g. Decimal("0.01"). -# TODO: задайте число знаков после запятой и шаг квантования (используйте своё -# решение части 2) -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) -# Column headers of the table produced by get_storage_str_representation, -# left to right. The width of each column is not fixed here -- it is -# measured per call from the data (see the function). -# TODO: задайте заголовки столбцов таблицы -TABLE_HEADERS: Final[tuple[str, ...]] = () +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) -def normalize_price(price: Decimal) -> Decimal: - """Round a price to the precision every stored record uses. +TABLE_HEADERS: Final[tuple[str, ...]] = ("ID", "name", "price", "quantity") - Args: - price: The raw price amount. - Returns: - ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, - with halves rounded up. - """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return Decimal(0) +def normalize_price(price: Decimal) -> Decimal: + return price.quantize(PRICE_STEP, rounding=ROUND_HALF_UP) def normalize_product_name(name: str) -> str: - """Reduce a product name to the canonical form the store keeps. - - Args: - name: The raw product name. - - Returns: - ``name`` with every leading and trailing whitespace character - removed, every internal run of whitespace (spaces, tabs and the - like) collapsed to a single space, and the rest lower-cased. For - example ``"abc def\tghi\tjkl"`` becomes ``"abc def ghi jkl"``. - The result is an empty string when ``name`` holds nothing but - whitespace. - """ - # TODO: реализуйте функцию - return "" + res = [word.lower() for word in name.split()] + return " ".join(res) # TODO: при необходимости добавьте свои вспомогательные функции def get_storage_str_representation(storage: list[Product]) -> str: - """Render the product store as a text table with data-sized columns. - - The table has the columns named by :data:`TABLE_HEADERS` -- id, name, - price and quantity. Each column is made exactly as wide as the longest - value it carries in this call (its header counted), so the columns - line up when the string is printed to a terminal and no value is ever - truncated. - - Args: - storage: The product store to render. - - Returns: - A multi-line string: a header row, a dashed separator row, then - one row per product in ``storage`` in list order. When ``storage`` - is empty only the header and separator rows are returned, sized to - the header labels. - """ - # TODO: реализуйте функцию - return "" + rows = [ + [ + str(product[PRODUCT_ID_INDEX]), + product[NAME_INDEX], + str(product[PRICE_INDEX]), + str(product[QUANTITY_INDEX]), + ] + for product in storage + ] + widths = [ + max(len(TABLE_HEADERS[i]), *(len(row[i]) for row in rows)) + if rows + else len(TABLE_HEADERS[i]) + for i in range(len(TABLE_HEADERS)) + ] + + header_line = ( + "| " + + " | ".join( + TABLE_HEADERS[i].ljust(widths[i]) for i in range(len(TABLE_HEADERS)) + ) + + " |" + ) + sep_line = "|" + "|".join("-" * (w + 2) for w in widths) + "|" + data_lines = [ + "| " + + " | ".join(row[i].ljust(widths[i]) for i in range(len(TABLE_HEADERS))) + + " |" + for row in rows + ] + return "\n".join([header_line, sep_line, *data_lines]) From 9ddfe92c4af3d374d573a6a4a5aedcc3d3399f6d Mon Sep 17 00:00:00 2001 From: Elena Krivchanskaya Date: Thu, 15 Oct 2026 10:39:17 +0300 Subject: [PATCH 16/16] Update snowflake.py --- src/part1/snowflake.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/part1/snowflake.py b/src/part1/snowflake.py index 1668befb..3a3512d0 100644 --- a/src/part1/snowflake.py +++ b/src/part1/snowflake.py @@ -28,7 +28,7 @@ def read_current_millis(epoch_ms: int) -> int: - return int(time.time()) * 1000 - epoch_ms - EPOCH_MS_DEFAULT + return int(time.time() * 1000) - epoch_ms - EPOCH_MS_DEFAULT def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> int: @@ -58,7 +58,7 @@ def generate_snowflake_id( print(f"sequence_id must be in [0, {SEQUENCE_ID_MAX}], but it is {sequence_id}") return None - epoch_ms = int(time.time()) * 1000 - EPOCH_MS_DEFAULT + epoch_ms = int(time.time() * 1000) - EPOCH_MS_DEFAULT if not (0 <= epoch_ms < TIMESTAMP_MS_MAX): print("overflow") return None