A Level Computer Science OCR Practice Exam

What problem does Dijkstra's Algorithm primarily solve?

1. Finding the shortest path in a graph

2. Sorting elements in ascending order

3. Determining the minimum spanning tree

4. Calculating factorial numbers

The correct answer is: Finding the shortest path in a graph

Dijkstra's Algorithm is designed specifically to find the shortest path between nodes in a weighted graph, which means it identifies the least costly or shortest route from a starting point to one or more target points. This algorithm is particularly effective for graphs with non-negative weights, as it systematically evaluates the paths and their costs, ensuring that the shortest path is determined in an efficient manner. The other options pertain to different algorithmic tasks. Sorting elements in ascending order is a distinct operation handled by sorting algorithms like quicksort or mergesort. The minimum spanning tree problem involves finding a subset of edges that connects all vertices in a graph without any cycles and with the minimum total edge weight, which is addressed by algorithms such as Prim's or Kruskal's. Lastly, calculating factorial numbers is a mathematical computation not related to graph theory or pathfinding. Hence, the correct identification of Dijkstra's Algorithm as a solution for finding the shortest path in a graph is accurate and reflects its primary application in computer science.