Quicksort is one of the earliest and most famous algorithms. It was invented and analyzed
by Tony Hoare around 1960. This was before the big-O notation was used to analyze algorithms.
Hoare invented the algorithm while an exchange student at Moscow State University while studying
probability under Kolmogorov—one of the most famous researchers in probability theory. The analysis
we will cover is different from what Hoare used in his original paper, although we will mention how
he did the analysis.