In quick sort, for sorting n elements, the (n/4)th smallest element is selected as pivot using an O(n) time algorithm. What is the worst case time complexity of the quick sort?

(A) (n)
(B) (nLogn)
(C) (n^2)
(D) (n^2 log n)
(A) A
(B) B
(C) C
(D) D


Answer: (B)

Explanation: The recursion expression becomes:

T(n) = T(n/4) + T(3n/4) + cn

After solving the above recursion, we get (nLogn).

Quiz of this Question