☕ Learn System Design?
AWS has an amazing, free series on System Design! Plus, a solution to our last coding interview question and a new interview question by Facebook!
Hey Guys,
Really sorry for missing the emails last week!
Unfortunately I ended up catching COVID (right when vaccines are rolling out of course), and was pretty much knocked out for all of last week.
Feeling a lot better now, so we’re back to it!
Thank you for your patience!
Tech Snippets
AWS’s This is My Architecture series is pretty fantastic. CTOs of various companies come and discuss how they’ve architected their systems.
My favorite video so far has been on Nordstrom’s Event-Sourced Serverless Architecture.
You can view the full playlist here.
The videos are by AWS, so they do shill their service a bit haha. But the concepts can be applied to any cloud provider!
Amazing article on Software Engineering compensation in Europe.
Software Engineering compensation can be split into three groups
Companies only benchmarking against local competition - Non-tech companies that view engineering as a “cost center”.
Companies benchmarking against all local companies - Companies like Disney, Nike, Booking, etc. These companies pay better but still aren’t tech companies. They’re not competing for the best engineering talent.
Companies benchmarking on a regional/global scale - Big Tech companies like Facebook/Google are in this grouping. These companies invest the most in engineering talent.
COVID-19 has been great for European Software Engineering salaries as Big Tech companies have been shifting more roles to the EU. Stripe, Spotify and Coinbase are a couple examples of companies that are going much harder on European roles.
Interview Question
You are given the root of a binary tree.
We define the “difference” of nodes A and B as
difference = |A.val - B.val|
Find the largest difference between any two nodes A and B in the tree, as long as A is an ancestor of B.
Here’s the question in LeetCode.
We’ll send a detailed solution tomorrow, so make sure you move our emails to primary, so you don’t miss them!
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Previous Solution
As a refresher, here’s the last question
You are given the root of a Binary Search Tree and an integer k.
Return the kth smallest element in the BST.
Here’s the question in LeetCode.
Solution
We can solve this question with an iterative in-order (smallest to largest) traversal.
If you don’t know how to implement an iterative in-order traversal, check this out.
While we run our traversal, we use a counter variable to keep track of how many nodes we’ve processed.
Once we’re on the kth node, we return the value.
Can you analyze the time complexity of our solution?
Reply back with your estimate!
We’ll tell you if you’re correct (or we’ll tell you the answer if you’re wrong).