Quicksort, given 3 values, how can I get to 9 operations? -


well, want use quick sort on given 3 values, doesn't matter values, how can worst case 9 operations?

can draw tree , show how show nlogn , n^2 operations? i've tried find on internet, still didnt manage draw 1 show that.

the worst case complexity of quick sort depends on chosen pivot. if pivot chosen leftmost or rightmost element. worst case complexity occur in following cases:

1) array sorted in same order.

2) array sorted in reverse order.

3) elements same (special case of case 1 , 2).

since these cases occur frequently, pivot chosen randomly. choosing pivot randomly chances of worst case reduced.

the analysis of quicksort algorithm explained in this blogpost khan academy.


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