Hey,
Here is the pseudocode of quicksort. It can be observed that there
are as many as (n-1) unresolved stack calls in the worst case. Now, how
do i reduce this unresolved stack calls? what modifications should I
make?
procedure QuickSort(L[0:n-1], low, high) recursive
Input: L[0:n-1] (a list of size n), low, high (integers)
Output: L[low:high] is sorted
if high > low then
Partition(L[0:n-1], low, high, position)
QuickSort(L[0:n-1], low, position - 1)
QuickSort(L[0:n-1], position + 1, high)
endif
end QuickSort
thanks,
Haran
2  2944  nk*****@gmail.c om wrote: Hey,
Here is the pseudocode of quicksort. It can be observed that there
are as many as (n-1) unresolved stack calls in the worst case. Now, how
do i reduce this unresolved stack calls? what modifications should I
make?
procedure QuickSort(L[0:n-1], low, high) recursive
Input: L[0:n-1] (a list of size n), low, high (integers)
Output: L[low:high] is sorted
if high > low then
Partition(L[0:n-1], low, high, position)
QuickSort(L[0:n-1], low, position - 1)
QuickSort(L[0:n-1], position + 1, high)
endif
end QuickSort
I would expect only log2(n) levels of recursion for a quicksort of n
items. So I would change the pseudocode to be a less recursive
implementation.
Greg nk*****@gmail.c om wrote: Hey,
Here is the pseudocode of quicksort. It can be observed that there
are as many as (n-1) unresolved stack calls in the worst case. Now, how
do i reduce this unresolved stack calls? what modifications should I
make?
procedure QuickSort(L[0:n-1], low, high) recursive
Input: L[0:n-1] (a list of size n), low, high (integers)
Output: L[low:high] is sorted
if high > low then
Partition(L[0:n-1], low, high, position)
QuickSort(L[0:n-1], low, position - 1)
QuickSort(L[0:n-1], position + 1, high)
endif
end QuickSort
thanks,
Haran
Obvious homework question and nothing to do with C++ either.
Obviously you weren't paying to much attention in class, had you been
you would have known to convert the tail recursive call into a loop.
john This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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