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Randomized version of quicksort

Open anay07 opened this issue 6 years ago • 6 comments

DESCRIPTION

Randomized version of quicksort is mostly implemented in real life and is missing in the repo as it is the randomized quicksort which gives it the worst case O(nlogn) complexity and not the naive implementation.

STEPS TO REPRODUCE

EXPECTED OUTCOME

Code of randomized quicksort will be added.

ACTUAL OUTCOME

Proposed Solution [optional]

I will like to add the randomized quicksort in the quicksort folder.

anay07 avatar Dec 07 '17 11:12 anay07

@anay07 , it would be better if you can show me some graph of this randomized quick sort

prateekiiest avatar Dec 07 '17 12:12 prateekiiest

@prateekiiest ,In randomized quicksort chooses the pivot at random (and also can shuffle the array at start) .

Doing this can some significant change as shown in below graphs Here are some comparison graphs for different input cases : 1)Sorted(Reverse) image image We can see there is significant difference in this case

2)Sorted image image We can see the difference is not so significant in this case

anay07 avatar Dec 07 '17 15:12 anay07

How about considering the distribution of the elements of the array? say quick sort on array of a normal distribution and on an array of uniform distribution ?

Both cases let Pivot choice be random.

prateekiiest avatar Dec 08 '17 08:12 prateekiiest

@anay07 did you send a PR for this ?

prateekiiest avatar Dec 29 '17 14:12 prateekiiest

Not till now as I was not assigned the same . Also I found that quicksort will not be affected by the distribution ( unless there are many duplicated values or if we know the range of distribution of number (as we can use bucket sort in this case which is faster than quicksort) )

anay07 avatar Dec 30 '17 07:12 anay07

I would like to contribute to this.

vasugr avatar Dec 05 '18 05:12 vasugr