Comments on: Mergesort and Quicksort with Dynamic Languages

By: cazacugmihai

cazacugmihai — Thu, 21 May 2009 07:15:33 +0000

——-GROOVY QUICKSORT————–

def quickSort(List lst) {
if (lst.size() <= 1) return lst
def (less, greater) = [[], []]
def pivot = lst.remove(new Random().nextInt(lst.size()))
lst.each {
if (it < pivot) less << it
else greater << it
}
quickSort(less) + pivot + quickSort(greater)
}

Instead of random parameter you can use (list.size() / 2)

By: Vincedel

Vincedel — Wed, 15 Apr 2009 18:07:20 +0000

Hey, cool tips. Perhaps I’ll buy a bottle of beer to that person from that forum who told me to visit your blog

By: admin

admin — Mon, 23 Mar 2009 16:18:57 +0000

Thanks for the submission George

By: vortex7

vortex7 — Sun, 22 Mar 2009 23:50:56 +0000

This is a working and clear groovy mergsort
def ms(lst){
  def sz=lst.size()
  if(sz <= 1)
    return lst

  def half = (int)(sz/2)
  def lft = ms(lst[0..   def rht = ms(lst[half..sz-1])
  def rcnt = 0
  def rlen = sz -half
  def result =[]
  lft.each {lf->
    while (rcnt < rlen && rht[rcnt] <= lf)
      result += rht[rcnt++]
    result += lf
  }
  while (rcnt < rlen)
    result += rht[rcnt++]
  return result
}

sl=[3,88,5,3,2,1,-2,2]
println ms(sl)