MongoDB prep

MongoDB Mid-level (3–5 years) Coding / DSA

#16

How do you perform topological sort on a directed acyclic graph? — MongoDB interview

Reported in MongoDB USA engineering loops. Graph algorithm for task scheduling, build systems, and course prerequisites.

Medium Read answer →

MongoDB Mid-level (3–5 years) System design

#17

Explain the CAP theorem and what it means for distributed systems — MongoDB interview

Reported in MongoDB USA engineering loops. Classic system design question asked at US big-tech and fintech on-site loops.

Medium Read answer →

MongoDB Mid-level (3–5 years) Coding / DSA

#18

How many distinct ways can you climb n stairs taking 1 or 2 steps at a time? — MongoDB interview

Reported in MongoDB USA engineering loops. Introductory dynamic programming problem isomorphic to Fibonacci.

Medium Read answer →

MongoDB Mid-level (3–5 years) Coding / DSA

#19

Design and implement an LRU cache with O(1) get and put — MongoDB interview

Reported in MongoDB USA engineering loops. Hash map plus doubly linked list problem bridging DSA and system components.

Hard Read answer →

MongoDB Mid-level (3–5 years) Coding / DSA

#20

Solve the 0/1 knapsack problem with dynamic programming — MongoDB interview

Reported in MongoDB USA engineering loops. Classic DP testing tabulation, space optimization, and item selection reconstruction.

Hard Read answer →

MongoDB Mid-level (3–5 years) Coding / DSA

#21

Explain and implement Dijkstra's algorithm for shortest paths — MongoDB interview

Reported in MongoDB USA engineering loops. Graph algorithm for non-negative edge weights using priority queue.

Hard Read answer →

MongoDB Mid-level (3–5 years) System design

#22

Design a URL shortening service — MongoDB interview

Reported in MongoDB USA engineering loops. Foundational system design covering APIs, encoding, storage, and read-heavy scaling.

Medium Read answer →