Walrus Operator (:=)

Without walrus - assign then test: With walrus - assign and test simultaneously: Avoiding Repeat Computation The walrus operator shines when you need to use a computed value in both a condition and the body: In List Comprehensions Walrus is particularly useful in list comprehensions when both the condition and the value need a computed result: Compute once, use twice in the comprehension. Interview Applications In interviews, walrus can make solutions more concise, but use it judiciously. Clarity trumps cleverness: BFS with level tracking: Chained Comparisons Python allows chaining comparison operators, which reads naturally and is more efficient than using "and" to combine conditions: Common interview applications: Grid bounds checking (very common): Sliding window bounds: Interview Patte