Interview Q&A / Data Structures & Algorithms
Data Structures & Algorithms interview questions
Arrays, linked lists, hashing, trees and patterns, with line-by-line code and complexity.
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- How do you implement merge sort in JavaScript?
Recursively split the array into two halves until single elements remain, then merge the sorted halves by repeatedly taking the smaller front element. It runs in O(n log n) time with O(n) extra space.
BeginnerQuick answerCoding1 min read - What happens if a recursive function has no base case?
It keeps calling itself, each call adds a frame to the call stack, and eventually the stack runs out of space. JavaScript throws a RangeError: Maximum call stack size exceeded.
BeginnerQuick answer1 min read