Airbnb QA Engineer Interview Questions

Airbnb needs a mechanism to report the most recent URLs that have generated certain status codes quickly.You are tasked with implementing a log manager based on a sliding window that can keep track of the last K status codes returned by the API endpoints.- def record_status(self, url: str, status_code: int) -> None: Records the status code for the corresponding URL.
- def get_recent_status(self, url: str, K: int) -> List[int]: Retrieves the last K status codes for the provided URL.Example 1:
Input: record_status('http://airbnb.com', 200)
Input: get_recent_status('http://airbnb.com', 1)
Output: [200]
Explanation: The last status code for the URL is 200. Example 2:
Input: record_status('http://airbnb.com', 500)
Input: record_status('http://airbnb.com', 404)
Input: get_recent_status('http://airbnb.com', 2)
Output: [500, 404]
Explanation: Returns the last two status codes recorded for this URL.Constraints:
- 1 <= K <= 100
- 1 <= status_code <= 599
- The URL string is at most 100 characters long.

Airbnb needs to ensure that a user's booking flow is correctly validated against the current state of available listings.Given a binary tree where each node represents a booking in a timeline of user actions, write a method that traverses the tree to validate the actions taken by the user.- def validate_booking_flow(self, root: Optional[TreeNode]) -> bool:: Returns True if the booking process is valid, False otherwise.Example 1:
Input: root = [2,1,3]
Output: True
Explanation: The booking sequence is valid as it follows the ordering of node values. Example 2:
Input: root = [5,1,4,null,null,3,6]
Output: False
Explanation: The booking sequence is invalid due to the left child being greater than the parent.Constraints:
- 0 <= number of nodes <= 1000
- -10^5 <= node.val <= 10^5

Airbnb's continuous integration (CI) system must accurately report flaky tests that can lead to unreliable build statuses. You need to design a system to track test results over multiple runs to identify flaky behavior.- def report_result(self, test_name: str, result: bool) -> None: Records the result of a test run.
- def is_flaky(self, test_name: str) -> bool: Returns True if the test has shown flaky results, False otherwise.Example 1:
Input: report_result('login_test', True)
Input: report_result('login_test', False)
Input: is_flaky('login_test')
Output: True
Explanation: The test passed and failed, indicating flakiness. Example 2:
Input: report_result('search_test', True)
Input: is_flaky('search_test')
Output: False
Explanation: The test has only passed once and is not flaky.Constraints:
- At most 1000 different test names.
- The system maintains results for up to 50 runs per test.