private static void DownHeap(IndexedSortable s, int b, int i, int N)
{
for (int idx = i << 1; idx < N; idx = i << 1)
{
if (idx + 1 < N && s.Compare(b + idx, b + idx + 1) < 0)
{
if (s.Compare(b + i, b + idx + 1) < 0)
{
s.Swap(b + i, b + idx + 1);
}
else
{
return;
}
i = idx + 1;
}
else
{
if (s.Compare(b + i, b + idx) < 0)
{
s.Swap(b + i, b + idx);
i = idx;
}
else
{
return;
}
}
}
}
private static void Fix(IndexedSortable s, int p, int r)
{
if (s.Compare(p, r) > 0)
{
s.Swap(p, r);
}
}
public void Sort(IndexedSortable s, int p, int r, Progressable rep)
{
int N = r - p;
// build heap w/ reverse comparator, then write in-place from end
int t = int.HighestOneBit(N);
for (int i = t; i > 1; i = (int)(((uint)i) >> 1))
{
for (int j = (int)(((uint)i) >> 1); j < i; ++j)
{
DownHeap(s, p - 1, j, N + 1);
}
if (null != rep)
{
rep.Progress();
}
}
for (int i_1 = r - 1; i_1 > p; --i_1)
{
s.Swap(p, i_1);
DownHeap(s, p - 1, 1, i_1 - p + 1);
}
}
public virtual void Swap(int i, int j)
{
Assert.True("Expected fewer than " + maxswp + " swaps", ++swaps
< maxswp);
s.Swap(i, j);
}
private static void SortInternal(IndexedSortable s, int p, int r, Progressable rep
, int depth)
{
if (null != rep)
{
rep.Progress();
}
while (true)
{
if (r - p < 13)
{
for (int i = p; i < r; ++i)
{
for (int j = i; j > p && s.Compare(j - 1, j) > 0; --j)
{
s.Swap(j, j - 1);
}
}
return;
}
if (--depth < 0)
{
// give up
alt.Sort(s, p, r, rep);
return;
}
// select, move pivot into first position
Fix(s, (int)(((uint)(p + r)) >> 1), p);
Fix(s, (int)(((uint)(p + r)) >> 1), r - 1);
Fix(s, p, r - 1);
// Divide
int i_1 = p;
int j_1 = r;
int ll = p;
int rr = r;
int cr;
while (true)
{
while (++i_1 < j_1)
{
if ((cr = s.Compare(i_1, p)) > 0)
{
break;
}
if (0 == cr && ++ll != i_1)
{
s.Swap(ll, i_1);
}
}
while (--j_1 > i_1)
{
if ((cr = s.Compare(p, j_1)) > 0)
{
break;
}
if (0 == cr && --rr != j_1)
{
s.Swap(rr, j_1);
}
}
if (i_1 < j_1)
{
s.Swap(i_1, j_1);
}
else
{
break;
}
}
j_1 = i_1;
// swap pivot- and all eq values- into position
while (ll >= p)
{
s.Swap(ll--, --i_1);
}
while (rr < r)
{
s.Swap(rr++, j_1++);
}
// Conquer
// Recurse on smaller interval first to keep stack shallow
System.Diagnostics.Debug.Assert(i_1 != j_1);
if (i_1 - p < r - j_1)
{
SortInternal(s, p, i_1, rep, depth);
p = j_1;
}
else
{
SortInternal(s, j_1, r, rep, depth);
r = i_1;
}
}
}