bat/tests/syntax-tests/highlighted/AWK/quicksort.awk

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2020-09-14 10:43:44 +02:00
# quicksort.awk --- Quicksort algorithm, with user-supplied
# comparison function
#
# Arnold Robbins, arnold@skeeve.com, Public Domain
# January 2009
# quicksort --- C.A.R. Hoare's quicksort algorithm. See Wikipedia
# or almost any algorithms or computer science text.
#
# Adapted from K&R-II, page 110
function quicksort(data, left, right, less_than, i, last)
{
 if (left >= right) # do nothing if array contains fewer
 return # than two elements
 quicksort_swap(data, left, int((left + right) / 2))
 last = left
 for (i = left + 1; i <= right; i++)
 if (@less_than(data[i], data[left]))
 quicksort_swap(data, ++last, i)
 quicksort_swap(data, left, last)
 quicksort(data, left, last - 1, less_than)
 quicksort(data, last + 1, right, less_than)
}
# quicksort_swap --- helper function for quicksort, should really be inline
function quicksort_swap(data, i, j, temp)
{
 temp = data[i]
 data[i] = data[j]
 data[j] = temp
}