/// <summary>
/// Copies elements from [begin,end) to [target-(end-begin), target), starting with *(target-1) = *(end-1),
/// and progressing backwards towards begin. Note that although elements are copied in reverse order, the order
/// of elements is not changed.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="begin"></param>
/// <param name="end"></param>
/// <param name="target"></param>
public static void CopyBackward <T>(BidirectionalIterator <T> begin, BidirectionalIterator <T> end, BidirectionalIterator <T> targetEnd)
{
targetEnd = IteratorUtil.Clone(targetEnd);
end = IteratorUtil.Clone(end);
while (!begin.Equals(end))
{
end.MovePrev();
targetEnd.MovePrev();
targetEnd.Write(end.Read());
}
}
public static void ReverseCopy <T>(BidirectionalIterator <T> begin, BidirectionalIterator <T> end, OutputIterator <T> dest)
{
end = IteratorUtil.Clone(end);
dest = IteratorUtil.Clone(dest);
while (!begin.Equals(end))
{
end.MovePrev();
dest.Write(end.Read());
dest.MoveNext();
}
}
public static bool NextPermutation <T>(BidirectionalIterator <T> begin, BidirectionalIterator <T> end,
Functional.BinaryPredicate <T> func)
{
if (begin.Equals(end))
{
return(false);
}
if (IteratorUtil.IsOneElementRange(begin, end))
{
return(false);
}
BidirectionalIterator <T> i = IteratorUtil.Clone(end);
i.MovePrev();
for (;;)
{
BidirectionalIterator <T> ii = IteratorUtil.Clone(i);
i.MovePrev();
T i_value = i.Read();
if (func(i_value, ii.Read()))
{
BidirectionalIterator <T> j = IteratorUtil.Clone(end);
for (j.MovePrev(); !func(i_value, j.Read()); j.MovePrev())
{
;
}
IteratorUtil.Swap(i, j);
Reverse(ii, end);
return(true);
}
if (i.Equals(begin))
{
Reverse(begin, end);
return(false);
}
}
}
public static bool NextPermutation <T>(BidirectionalIterator <T> begin, BidirectionalIterator <T> end, IComparer <T> comparer)
{
if (begin.Equals(end))
{
return(false);
}
if (IteratorUtil.IsOneElementRange(begin, end))
{
return(false);
}
BidirectionalIterator <T> i = IteratorUtil.Clone(end);
i.MovePrev();
for (;;)
{
BidirectionalIterator <T> ii = IteratorUtil.Clone(i);
i.MovePrev();
T i_value = i.Read();
if (comparer.Compare(i_value, ii.Read()) == -1)
{
BidirectionalIterator <T> j = IteratorUtil.Clone(end);
for (j.MovePrev(); comparer.Compare(i_value, j.Read()) != -1; j.MovePrev())
{
;
}
IteratorUtil.Swap(i, j);
Reverse(ii, end);
return(true);
}
if (i.Equals(begin))
{
Reverse(begin, end);
return(false);
}
}
}