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Need help with quicksort

I know this is kind of stupid but I was trying to implement quicksort in Python and it runs into an infinite loop can anyone tell me what's wrong??The partition subroutine works perfectly....The error is in quicksort..Here's the code

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     def QuickSort(A,p,r):
          if p < r:
              q = Partition(A,p,r)
              QuickSort(A,0,q)
              QuickSort(A,q+1,r)

    def Partition(A, l, r):
        p = A[l]
        i = l+1
        for j in range(l+1,r):
            if A[j] < p:
                A[j],A[i] = A[i],A[j]
                i += 1
        A[l],A[i-1] = A[i-1],A[l]
     return A.index(p)
#ComputerScience #HelpMe! #Help #brillianthelp #Pleasehelp

Note by Eddie The Head
3 years, 2 months ago

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def Quicksort(A,p,r):
    if p < r:
        q = Partition(A,p,r)
        Quicksort(A,p,q-1) #Mistake is here
        Quicksort(A,q+1,r)
    return A
I am reasonably sure that this is what would work. @josh silverman, can you confirm? – Trevor B. · 3 years, 2 months ago

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@Trevor B. – to start, your Quicksort doesn't return anything – Josh Silverman Staff · 3 years, 2 months ago

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@Trevor B. – Fixed!!Thanks a lot.....It feels so frustrated to do stupid mistakes on a known problem............ – Eddie The Head · 3 years, 2 months ago

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@Thaddeus Abiy @Ammar Fathin Sabili @Trevor B. Please help!!CS is one of the subjects that I study the most but failing such a trivial and known question today is driving me mad! – Eddie The Head · 3 years, 2 months ago

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@Eddie The Head – @Chung Gene Keun – Eddie The Head · 3 years, 2 months ago

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