Duplicate Finder Efficiency Quiz Quiz

1. Algorithm Choice

   Which data structure generally offers the most efficient way to detect duplicates in a shopping list if order is not important and the list is very large?

   1. A. An array, using nested loops for comparison.
   2. B. A sorted array, using binary search.
   3. C. A hash set (or dictionary), checking for existing keys.
   4. D. A linked list, traversing the list for each item.
   5. E. A tree, building a search tree.

2. Nested Loops Efficiency

   What is the time complexity of using nested loops to compare each item in a shopping list of 'n' items against every other item to find duplicates?

   1. A. O(n)
   2. B. O(log n)
   3. C. O(n log n)
   4. D. O(n^2)
   5. E. O(1)

3. HashSet Efficiency

   What is the average time complexity of adding an element to a hash set (assuming a good hash function) when checking for duplicates in a shopping list?

   1. A. O(n)
   2. B. O(log n)
   3. C. O(n log n)
   4. D. O(n^2)
   5. E. O(1)

4. Space Complexity Trade-off

   When comparing nested loops and a hash set for duplicate detection, which method typically requires significantly more memory?

   1. A. Nested loops, because they store all items multiple times.
   2. B. Nested loops, but only for very large lists.
   3. C. The hash set, as it needs to store the shopping list items plus the hash table itself.
   4. D. Neither, they use approximately the same amount of memory.
   5. E. It depends on the speed of the processor.

5. Sorted Array Efficiency

   If a shopping list is already sorted, which method is the most efficient to find duplicates?

   1. A. Using nested loops for comparison.
   2. B. A hash set (or dictionary), checking for existing keys.
   3. C. Linear scan, comparing adjacent elements.
   4. D. A tree, building a search tree.
   5. E. Random selection.

6. Small List Scenario

   For a very small shopping list (e.g., less than 10 items), which duplicate detection method is likely to be the fastest in practice due to lower overhead?

   1. A. Using a hash set.
   2. B. Using nested loops.
   3. C. Sorting the list and using binary search.
   4. D. Sorting the list and scanning adjacent elements.
   5. E. Using a complex algorithm.

7. Code Snippet Efficiency

   Consider the following pseudo-code: `for i from 0 to n-1: for j from i+1 to n: if list[i] == list[j]: print 'Duplicate'`. What's the dominant factor affecting its efficiency?

   1. A. The speed of the 'print' statement.
   2. B. The size of the shopping list, 'n'.
   3. C. The number of duplicates in the list.
   4. D. The type of items in the list.
   5. E. None of the above.

8. Choosing the Right Tool

   A shopping list is received from an external source, and duplicate detection is a one-time operation. Which of the following is the MOST important factor when choosing an algorithm?

   1. A. Minimizing memory usage at all costs.
   2. B. Minimizing code complexity, even if it's slightly slower.
   3. C. Achieving the absolute fastest execution time, regardless of code complexity.
   4. D. Reducing the cost of sorting first, then searching.
   5. E. Decreasing compilation time.

9. Hash function impacts

   How can a poorly implemented hash function affect the efficiency of duplicate detection using a hash set?

   1. A. It will not affect the efficiency.
   2. B. It can lead to frequent collisions, degrading performance towards O(n) for insertions and lookups.
   3. C. It can reduce the memory usage of the hash set.
   4. D. It can make the code unreadable.
   5. E. It can increase the speed of lookups.

10. Best case scenarios

    In which scenario using nested loops perform efficiently?

    1. A. When comparing images.
    2. B. When comparing very small datasets.
    3. C. When order is important.
    4. D. When having millions of items in the array.
    5. E. Nested loops will never perform efficiently.