What is the best way to choose a pivot in Quicksort?

What is the best way to choose a pivot in Quicksort?

Choosing a good pivot is crucial for the efficiency of Quicksort. Common strategies include picking the first element, the last element, the median, or a random element.

What are the pros and cons of each pivot selection method?

1. First/Last Element: Simple but can lead to poor performance on sorted data. 2. Median: More balanced but requires extra computation. 3. Random: Helps avoid worst-case scenarios but adds randomness.

How does the choice of pivot affect the time complexity?

The choice of pivot affects the partitioning of the array. A good pivot leads to balanced partitions, resulting in O(n log n) time complexity, while a poor choice can degrade it to O(n²).

Can you give an example of a good pivot choice?

Sure! If you have an array like [3, 6, 8, 10, 1, 2, 1], choosing the median (which is 3 in this case) would likely lead to more balanced partitions.