| Exam Board | OCR MEI |
|---|---|
| Module | D1 (Decision Mathematics 1) |
| Year | 2013 |
| Session | June |
| Marks | 8 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Sorting Algorithms |
| Type | Describing Sorting Algorithm Steps |
| Difficulty | Easy -1.8 This appears to be an incomplete question fragment showing only the initialization step of a sorting algorithm description. Such questions typically ask students to trace through a standard algorithm (bubble sort, quick sort, etc.) step-by-step with given data—a purely procedural task requiring only recall and careful execution of memorized rules, with no problem-solving or mathematical insight required. |
| Spec | 7.03j Sorting: bubble sort and shuttle sort |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| Dijkstra — C correct | B1 | Dijkstra – C correct |
| other working values correct | B1 | other working values |
| order of labelling correct | B1 | order of labelling |
| labels correct | B1 | labels; Note D and G could be labelled in reverse order |
| First 4 pairs: AB=13, ABC=26, ABCD=39, ABE=44 | B1 | first 4 pairs |
| Second 4 pairs: ABCF=35, ABCG=39, ABCDH=52, ABCGI=46 | B1 | second 4 pairs |
| [6] |
| Answer | Marks | Guidance |
|---|---|---|
| Answer | Marks | Guidance |
| Turn distances to times throughout the network. Add 10 mins to every arc incident upon C. (or do Dijkstra twice, once with C deleted, and compare with the adjusted time through C) | E1 | Explanations needed, not answers |
| E1 | any correct logic | |
| [2] |
## Question 3:
### Part (i)
| Answer | Marks | Guidance |
|--------|-------|----------|
| Dijkstra — C correct | B1 | Dijkstra – C correct |
| other working values correct | B1 | other working values |
| order of labelling correct | B1 | order of labelling |
| labels correct | B1 | labels; Note D and G could be labelled in reverse order |
| First 4 pairs: AB=13, ABC=26, ABCD=39, ABE=44 | B1 | first 4 pairs |
| Second 4 pairs: ABCF=35, ABCG=39, ABCDH=52, ABCGI=46 | B1 | second 4 pairs |
| | **[6]** | |
### Part (ii)
| Answer | Marks | Guidance |
|--------|-------|----------|
| Turn distances to times throughout the network. Add 10 mins to every arc incident upon C. (or do Dijkstra twice, once with C deleted, and compare with the adjusted time through C) | E1 | Explanations needed, not answers |
| | E1 | any correct logic |
| | **[2]** | |
---3 Let $j$ equal 1.\\
\hfill \mbox{\textit{OCR MEI D1 2013 Q3 [8]}}