Algorithms Cheat Sheet 2026

The 30 highest-yield Algorithms facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which algorithm finds all strongly connected components in a directed graph in O(V + E) time? → Kosaraju's
2. What is the key benefit of using shared vocabulary (e.g., agreed definitions for 'fast,' 'efficient') between technical and non-technical teams? → It reduces miscommunication and aligns expectations across stakeholders
3. A load balancer must distribute requests across servers so no server is overwhelmed. Consistent hashing is preferred over simple modular hashing because: → Adding or removing a server only remaps a fraction of keys instead of all keys
4. Floyd-Warshall algorithm solves which graph problem? → All-pairs shortest path
5. Which attack specifically targets the algorithm training pipeline by injecting malicious data to corrupt a machine learning model's behavior? → Data poisoning attack
6. When an algorithm unexpectedly degrades in production, what is the first communication priority? → Notify affected stakeholders promptly with impact scope and estimated resolution time
7. Which sorting algorithm is most suitable for sorting linked lists efficiently? → MergeSort
8. In supply chain risk management for software, what is a 'software bill of materials' (SBOM) used for? → Identifying all third-party components and their known vulnerabilities
9. An e-commerce site uses a hash function to map product IDs to storage slots for O(1) lookup. What is a key concern with this approach? → Hash collisions
10. When a search engine indexes the web, it visits pages by following links layer by layer. Which traversal algorithm does this resemble? → Breadth-First Search
11. Which quantitative technique calculates the expected value of additional information to decide whether further risk analysis is worth its cost? → Expected Value of Perfect Information (EVPI)
12. During risk prioritization, a team applies the Pareto principle. What does this suggest about risk distribution? → Roughly 80% of impact comes from 20% of risks
13. How do Algorithms professionals transfer knowledge from training to practice? → Through supervised practice, mentoring, gradual independence, and ongoing feedback
14. A genomics tool aligns a short DNA read against a reference genome of 3 billion bases. Which algorithmic technique makes this feasible? → BWT/FM-index allowing near O(m) lookup
15. What is the first step in risk assessment for Algorithms professionals? → Identifying potential hazards and vulnerabilities in the specific context
16. What is the 'no free lunch theorem' and its implication for algorithm research? → No single algorithm outperforms all others across every possible input distribution
17. Which search algorithm requires the input list to be sorted before it can be applied? → Binary Search
18. Which principle requires that the same algorithmic decision process be applied uniformly to individuals regardless of protected characteristics? → Procedural fairness
19. In a sorted array, if you double the number of elements, how many additional steps does Binary Search need? → 1 more step
20. Which risk response is most appropriate when the cost of mitigating a risk exceeds the expected loss from the risk occurring? → Acceptance
21. Which metric directly measures the number of independent paths through a program's control flow? → Cyclomatic complexity
22. Consider two L1 and L2 sorted lists. In the worst-case scenario, the number of comparisons required by my merge sort algorithm will be → L1+L2-1
23. What is the time complexity of accessing an element by index in a dynamic array (e.g., Python list)? → O(1)
24. An algorithm change reduced server costs by 40% but increased code complexity. How should this trade-off be communicated to stakeholders? → Present both the benefit and the maintenance risk with mitigation strategies
25. What is the Dijkstra Algorithm's running time? → O(|V|^2 + |E|)
26. What is the purpose of a 'smoke test' in algorithmic quality control? → To quickly verify the most critical functions work before deeper testing
27. Which of the following problems is NP-complete? → The Traveling Salesman Decision Problem
28. Which metric captures the percentage of known defects detected by a test suite before release? → Defect detection percentage (DDP)
29. How should an Algorithms professional respond to a compliance violation? → Report it promptly, investigate the root cause, and implement corrective actions
30. Which emerging U.S. regulatory requirement asks companies to disclose when consumers are interacting with an AI system rather than a human? → The AI Transparency Act (proposed)