Must-do problems: Sorting Algorithms

These are the sorting problems every placement candidate should be able to solve, from a plain sort to counting inversions and bucket gaps. Pick the idea first: merge, partition, counting or a key function. Trace a small input on paper, then check your program against every test.

1. 1.Sort the exam marksEasy
2. 2.Is the list already in orderEasy
3. 3.Swaps made by bubble sortEasy
4. 4.Selection sort after k roundsEasy
5. 5.Rank staff by salaryEasy
6. 6.Median response timeEasy
7. 7.Merge two sorted price listsEasy
8. 8.Count the inversionsMedium
9. 9.K-th largest scoreMedium
10. 10.Sort the three prioritiesMedium
11. 11.Sort by frequencyMedium
12. 12.Largest number from piecesMedium
13. 13.Merge overlapping bookingsMedium
14. 14.Sort by a given orderMedium
15. 15.Students scoring lowerMedium
16. 16.Smaller values to the rightHard
17. 17.Pairs with more than doubleHard
18. 18.Largest gap between sorted valuesHard
19. 19.Sort a nearly sorted listHard
20. 20.Fewest swaps to sortHard