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. Floyd-Warshall algorithm solves which graph problem? → All-pairs shortest path
3. Which sorting algorithm is most suitable for sorting linked lists efficiently? → MergeSort
4. How do Algorithms professionals transfer knowledge from training to practice? → Through supervised practice, mentoring, gradual independence, and ongoing feedback
5. What is the first step in risk assessment for Algorithms professionals? → Identifying potential hazards and vulnerabilities in the specific context
6. Which search algorithm requires the input list to be sorted before it can be applied? → Binary Search
7. In a sorted array, if you double the number of elements, how many additional steps does Binary Search need? → 1 more step
8. 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
9. What is the time complexity of accessing an element by index in a dynamic array (e.g., Python list)? → O(1)
10. What is the Dijkstra Algorithm's running time? → O(|V|^2 + |E|)
11. How should an Algorithms professional respond to a compliance violation? → Report it promptly, investigate the root cause, and implement corrective actions
12. What is the benefit of standardized digital reporting in Algorithms practice? → It ensures consistency, enables comparison, and facilitates regulatory compliance
13. What approach does the Coin Change problem use to find the minimum number of coins for a target amount? → Bottom-up DP filling amounts from 0 to target
14. Which graph traversal algorithm uses a queue as its primary data structure? → Breadth-First Search
15. Matrix Chain Multiplication DP minimizes what? → Total number of scalar multiplications
16. What condition must a directed graph satisfy to have a topological ordering? → It must have no cycles (be a DAG)
17. What is the time complexity of the classic 0/1 Knapsack DP solution with n items and capacity W? → O(nW)
18. What is the amortized time complexity of a single push operation on a dynamic array that doubles in size when full? → O(1)
19. Which graph algorithm uses a priority queue and is suitable for finding shortest paths in graphs with non-negative weights? → Dijkstra's
20. What is the worst-case time complexity of Bubble Sort? → O(n²)
21. Which DP problem asks for the length of the longest subsequence common to two strings? → Longest Common Subsequence
22. Why is it necessary to use a flowchart? → To plan a program before making it.
23. What is the time complexity of a single operation on a balanced binary search tree (e.g., AVL or Red-Black tree) for search, insert, or delete? → O(log n)
24. How should an Algorithms professional present complex information to non-experts? → Translate into accessible language, use visuals, and check for understanding
25. What is a bridge in an undirected graph? → An edge whose removal increases the number of connected components
26. Which of the following algorithms has a time complexity of n log (n)? → Insertion sort
27. What distinguishes greedy algorithms from dynamic programming? → Greedy makes locally optimal choices without revisiting; DP considers all subproblems
28. What is the benefit of interdisciplinary collaboration in Algorithms practice? → It brings diverse expertise and perspectives that improve outcomes and innovation
29. The recurrence T(n) = 2T(n/2) + O(n) describes which well-known algorithm's complexity? → Merge sort
30. What role does active listening play in Algorithms practice? → It ensures accurate understanding, demonstrates respect, and improves outcomes