useful awk functions

awklib.awk

function qsort(A, left, right,   i, last) {
	if (left >= right)
		return
	last = left
	for (i = left+1; i <= right; i++)
		if (A[i] < A[left])
		swap(A, ++last, i)
	swap(A, left, last)
	qsort(A, left, last-1)
	qsort(A, last+1, right)
}

function swap(A, i, j,   t) {
	t = A[i]; A[i] = A[j]; A[j] = t 
}