Epic Skills Assessment Algorithmic Problem Solving 4

Question 1

Which algorithm finds the shortest path in a weighted graph with non-negative edge weights?

Accepted Answer

Dijkstra's algorithm

Answer

Dijkstra's algorithm greedily processes the nearest unvisited vertex and is correct for graphs with non-negative weights.

Question 2

What is the defining property of a hash function used in a hash table?

Accepted Answer

It maps keys to fixed-size indices with ideally uniform distribution

Answer

A good hash function maps arbitrary keys to array indices uniformly, minimizing collisions without needing to be bijective.

Question 3

In a sliding window algorithm, what problem does the technique primarily solve?

Accepted Answer

Efficiently processing contiguous subarrays or substrings without recomputing from scratch

Answer

A sliding window maintains a range and updates it incrementally, reducing many O(n²) subarray problems to O(n).

Question 4

Which of the following is an example of a divide-and-conquer algorithm?

Accepted Answer

Merge sort

Answer

Merge sort splits the array in half, recursively sorts each half, and merges them—the classic divide-and-conquer pattern.

Question 5

What does it mean for a problem to be NP-complete?

Accepted Answer

It is in NP and every NP problem reduces to it in polynomial time

Answer

NP-complete problems are the hardest problems in NP: if any one can be solved in polynomial time, all NP problems can be.

Epic Skills Assessment Practice Test