**I need to make a quicksort algorithm but so that it uses only one list and does swaps inside of it. I managed to make it "sort" or position the first element but now i don't know how to implement the recursion. The biggest problem I'm having is how to recursively work on a part of the list instead of making the new one. Here is my code: -------------------------------------------------------------------------------** New code, same problem.
Here is my code. It does the job but gets stuck in the loop.
def qsort(n,l,g):
if l is None:
l=0
if g is None:
g=len(n)
if g-l<=1:
return n
print g-l
p=n[l]
i=1+l
j=1+l
for x in n[l+1:g]:
if x<p:
n[i],n[j]=n[j],n[i]
i+=1
j+=1
n[l],n[i-1]=n[i-1],n[l]
ls=0
le=i-1
gs=i
ge=j
print n
qsort(n,ls,le)
qsort(n,gs,ge)
Can someone give me any suggestions, I'm lost. Can't find whats wrong or how to fix it. Know its messy but cant do better atm :D
Write it like this:
def qsort(li, lo=None, hi=None):
if lo is None:
lo = 0
if hi is None:
hi = len(li) - 1
...
...
if hi - lo > 1:
qsort(## left half ##)
qsort(## right half ##)
lo and hi are the smallest and largest indexes you should look at in li, respectively.