Update receive_file.py (#8541)

* Update receive_file.py

Here are the changes I made:

Added the main() function and called it from if __name__ == "__main__" block. This makes it easier to test the code and import it into other programs.
Added socket.AF_INET as the first argument to socket.socket(). This specifies the address family to be used, which is necessary when using connect().
Changed print(f"{data = }") to print("Received:", len(data), "bytes"). This makes it clearer what's happening and how much data is being received.
Changed the final print statement to "Successfully received the file". This makes it more accurate and descriptive.
Moved the import statement to the top of the file. This is a common convention in Python.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

dynamic_programming/max_product_subarray.py

@@ -0,0 +1,53 @@
+def max_product_subarray(numbers: list[int]) -> int:
+    """
+    Returns the maximum product that can be obtained by multiplying a
+    contiguous subarray of the given integer list `nums`.
+
+    Example:
+    >>> max_product_subarray([2, 3, -2, 4])
+    6
+    >>> max_product_subarray((-2, 0, -1))
+    0
+    >>> max_product_subarray([2, 3, -2, 4, -1])
+    48
+    >>> max_product_subarray([-1])
+    -1
+    >>> max_product_subarray([0])
+    0
+    >>> max_product_subarray([])
+    0
+    >>> max_product_subarray("")
+    0
+    >>> max_product_subarray(None)
+    0
+    >>> max_product_subarray([2, 3, -2, 4.5, -1])
+    Traceback (most recent call last):
+        ...
+    ValueError: numbers must be an iterable of integers
+    >>> max_product_subarray("ABC")
+    Traceback (most recent call last):
+        ...
+    ValueError: numbers must be an iterable of integers
+    """
+    if not numbers:
+        return 0
+
+    if not isinstance(numbers, (list, tuple)) or not all(
+        isinstance(number, int) for number in numbers
+    ):
+        raise ValueError("numbers must be an iterable of integers")
+
+    max_till_now = min_till_now = max_prod = numbers[0]
+
+    for i in range(1, len(numbers)):
+        # update the maximum and minimum subarray products
+        number = numbers[i]
+        if number < 0:
+            max_till_now, min_till_now = min_till_now, max_till_now
+        max_till_now = max(number, max_till_now * number)
+        min_till_now = min(number, min_till_now * number)
+
+        # update the maximum product found till now
+        max_prod = max(max_prod, max_till_now)
+
+    return max_prod

file_transfer/receive_file.py

@@ -1,8 +1,9 @@
-if __name__ == "__main__":
-    import socket  # Import socket module
+import socket
 
-    sock = socket.socket()  # Create a socket object
-    host = socket.gethostname()  # Get local machine name
+
+def main():
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    host = socket.gethostname()
     port = 12312
 
     sock.connect((host, port))
@@ -13,11 +14,14 @@ if __name__ == "__main__":
         print("Receiving data...")
         while True:
             data = sock.recv(1024)
-            print(f"{data = }")
             if not data:
                 break
-            out_file.write(data)  # Write data to a file
+            out_file.write(data)
 
-    print("Successfully got the file")
+    print("Successfully received the file")
     sock.close()
     print("Connection closed")
+
+
+if __name__ == "__main__":
+    main()