Software Development Engineer, Buyer Abuse Prevention

Amazon

There is a robot on an m x n grid. The robot is initially located at the top-left corner (i.e., grid0). The robot tries to move to the bottom-right corner (i.e., gridm - 1). The robot can only move either down or right at any point in time. Given the two integers m and n, return the number of possible unique paths that the robot can take to reach the bottom-right corner. The test cases are generated so that the answer will be less than or equal to 2 * 109. For example, if m = 3 and n = 7, the expected output is 28. Explain your approach, provide code, and analyze the time and space complexity. Also discuss edge cases and alternative solutions using combinatorics.

Amazon

Let's design a turnstile. A turnstile is a type of gate which allows one person to pass at a time. Consider a turnstile at a subway station. There are two panels that rotate to allow a single person passage. The turnstile has two states, Locked and Unlocked, and the customer can either Push the turnstile or Insert a token/card. Here is the state transition table: | Event | Current State | Action | Next State | | :----- | :------------ | :------------- | :--------- | | Push | Locked | | Locked | | Token | Locked | Unlock | Unlocked | | Push | Unlocked | Pass through | Locked | | Token | Unlocked | (discarded) | Unlocked | Requirements: Model the state and behavior of a simple turnstile. Implement two methods: insert_token() push() Consider edge cases and error handling. What happens if someone tries to push without inserting a token? What happens if the system malfunctions? Example: turnstile = Turnstile() print(turnstile.state) # Output: Locked turnstile.push() print(turnstile.state) # Output: Locked turnstile.insert_token() print(turnstile.state) # Output: Unlocked turnstile.push() print(turnstile.state) # Output: Locked How would you approach this design and implementation, keeping in mind scalability, maintainability, and potential future extensions such as different types of tokens or remote unlocking?

Amazon

Why do you want to work at Amazon? To provide a comprehensive answer, consider the following aspects: Amazon's Mission and Values: How do Amazon's core values, such as customer obsession, innovation, bias for action, and ownership, resonate with your personal and professional values? Provide specific examples of how you've demonstrated similar values in your previous experiences. For instance, can you describe a situation where you went above and beyond to satisfy a customer, or when you took initiative to implement a novel solution to a challenging problem? Amazon's Culture of Innovation: Amazon is renowned for its innovative culture and willingness to experiment. How does this environment appeal to you? Are there any specific Amazon products, services, or initiatives that you find particularly inspiring or exciting? Perhaps you're impressed by Amazon Web Services (AWS), Amazon's foray into artificial intelligence with Alexa, or their advancements in logistics and delivery. Explain why these innovations capture your interest and how you believe you could contribute to future innovation at Amazon. Growth and Learning Opportunities: Amazon offers a wide range of opportunities for professional growth and development. What specific roles or career paths within Amazon are you interested in exploring, and why? Have you researched Amazon's internal training programs or mentorship opportunities? Discuss how you envision leveraging these resources to expand your skillset and advance your career within the company. For example, are you interested in moving into a leadership role, specializing in a particular technology, or working on a global scale? Your Skills and Experience: How do your skills and experience align with Amazon's needs and priorities? Identify specific projects or accomplishments from your past that demonstrate your ability to succeed in a fast-paced, demanding environment. Highlight any experience you have with technologies or methodologies that are relevant to Amazon's business, such as cloud computing, data analysis, machine learning, or agile development. Be prepared to discuss how your unique skills and experiences can contribute to Amazon's continued success. Can you quantify your accomplishments with metrics? Company Impact: What excites you about the potential to contribute to Amazon's impact on customers and the world? Consider how Amazon's products and services have transformed industries and improved people's lives. Are you drawn to the scale and scope of Amazon's operations, or the opportunity to work on projects that have a global reach? Express your enthusiasm for being part of a company that is constantly pushing boundaries and shaping the future.