Senior Software Engineer, Machine Learning, Google Ads

Google

Let's explore some string manipulation algorithms. Suppose you are given a string s and you need to reverse the order of words in the string. Each word is separated by a single space, and there are no leading or trailing spaces. For example, if the input string s is the sky is blue, the expected output is blue is sky the. Write a function that takes a string s as input and returns a new string with the words in reversed order. Explain your approach. What is the time and space complexity of your algorithm? Provide example test cases to demonstrate that your function works correctly, including edge cases such as an empty string or a string with only one word. As a follow-up, consider a more complex scenario where the input string s might contain leading or trailing spaces, or multiple spaces between words. How would you modify your algorithm to handle these cases while still producing the correct reversed word order? For instance, given the input hello world , the output should be world hello. Describe the changes needed and analyze the updated time and space complexity.

Google

Let's design a web proxy. Consider the following requirements: Basic Functionality: The proxy should be able to forward HTTP and HTTPS requests from clients to web servers and return the responses. Caching: Implement caching to reduce latency and bandwidth usage for frequently accessed resources. How would you handle cache invalidation? Security: The proxy should support HTTPS and protect client data. How would you handle SSL/TLS certificates? Scalability: The proxy should be able to handle a large number of concurrent connections. What architectural choices would you make to ensure scalability? Authentication: Implement basic authentication (username/password) to control access to certain websites. Logging: Log requests and responses for debugging and monitoring purposes. What information should be logged, and how would you manage log files? Blocking: Implement the functionality to block access to certain websites based on a blacklist. Discuss the architecture, components, and algorithms involved in building such a web proxy. Include considerations for performance, security, and maintainability. Provide example scenarios and solutions to potential challenges.

Google

Where do you see yourself in 5 years?