Coding Skills Flashcards
7 cards from real Mettl practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Coding Skills flashcards as text
Which of the following correctly describes a hash collision?
Answer: Two different keys produce the same hash value
A collision occurs when two distinct keys hash to the same index in the table.
What is the worst-case space complexity of recursive quicksort due to call stack usage?
Answer: O(n)
In the worst case (already sorted input), quicksort recurses n times, using O(n) stack space.
In Java, which keyword prevents a method from being overridden in a subclass?
Answer: final
Declaring a method 'final' prevents subclasses from overriding it.
What does a REST API use to indicate that a resource was successfully created?
Answer: HTTP 201 Created
HTTP 201 Created is the standard response for a successful POST that creates a new resource.
Which of the following is NOT a valid way to declare a variable in JavaScript (ES6+)?
Answer: def x = 5;
'def' is used in Python, not JavaScript; valid JS declarations use var, let, or const.
What is memoization primarily used for in programming?
Answer: Caching results of expensive function calls to avoid redundant computation
Memoization stores previously computed results so repeated calls with the same input return instantly.
In Git, what does `git stash` do?
Answer: Temporarily shelves uncommitted changes so the working directory is clean
git stash saves dirty working directory changes onto a stack so you can switch contexts cleanly.