Fixed window algorithm in Rest API - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize the fixed window counter dictionary.

Rest API

counters = [1]

Drag options to blanks, or click blank then click option'

Aset()

B[]

C{}

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using a list or set instead of a dictionary.

We use an empty dictionary {} to store counters for each client in the fixed window algorithm.

2fill in blank

medium

Complete the code to get the current timestamp in seconds.

Rest API

current_time = int(time.[1]())

Drag options to blanks, or click blank then click option'

Asleep

Btime

Cctime

Dlocaltime

Attempts:

3 left

💡 Hint

Common Mistakes

Using ctime() which returns a string, not a timestamp.

The time.time() function returns the current time in seconds since the epoch as a float. We convert it to int for whole seconds.

3fill in blank

hard

Fix the error in the condition that resets the window when the time window has passed.

Rest API

if current_time - counters[client_id]['start_time'] [1] window_size:

Drag options to blanks, or click blank then click option'

A<

B<=

C==

D>=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < or == which do not cover the full window expiration condition.

The window resets when the elapsed time is greater than or equal to the window size.

4fill in blank

hard

Fill both blanks to update the counter and reset the start time when the window expires.

Rest API

counters[client_id]['count'] = [1]
counters[client_id]['start_time'] = [2]

Drag options to blanks, or click blank then click option'

A1

Bcurrent_time

C0

Dwindow_size

Attempts:

3 left

💡 Hint

Common Mistakes

Resetting count to 0 instead of 1, or not updating start time.

When the window expires, reset the count to 1 for the new request and update the start time to the current time.

5fill in blank

hard

Fill all three blanks to increment the count, check if the request is allowed, and return the correct boolean.

Rest API

counters[client_id]['count'] [1] 1
if counters[client_id]['count'] [2] max_requests:
    return [3]
else:
    return True

Drag options to blanks, or click blank then click option'

A+=

B>

CFalse

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of > in the condition or returning True when blocking is needed.

Increment the count by 1. If count exceeds max requests, return False to block the request; otherwise, allow it.