public static bool BinarySearch <T>(
this ArrayIterator <T> first,
ArrayIterator <T> last,
T val,
Func <T, T, bool> comp
)
{
first = first.LowerBound(last, val, comp);
return(first.NotEqual(last) && comp(val, first.GetCurrent()) == false);
}
public static void EqualRange <T>(
this ArrayIterator <T> first,
ArrayIterator <T> last,
T val,
Func <T, T, bool> comp,
out ArrayIterator <T> lower,
out ArrayIterator <T> upper
)
{
lower = first.LowerBound(last, val, comp);
upper = lower.UpperBound(last, val, comp);
}
public static void InplaceMerge <T>(
this ArrayIterator <T> first,
ArrayIterator <T> middle,
ArrayIterator <T> last,
Func <T, T, bool> comp
)
{
if (first.Index >= middle.Index || middle.Index >= last.Index)
{
return;
}
if (last.Index - first.Index == 2)
{
if (comp(middle.GetCurrent(), first.GetCurrent()))
{
Swap(first, middle);
}
return;
}
ArrayIterator <T> firstCut;
ArrayIterator <T> secondCut;
if (middle.Index - first.Index > last.Index - middle.Index)
{
firstCut = first.GetAdvanced(first.Distance(middle) / 2);
secondCut = middle.LowerBound(last, firstCut.GetCurrent(), comp);
}
else
{
secondCut = middle.GetAdvanced(middle.Distance(last) / 2);
firstCut = first.UpperBound(middle, secondCut.GetCurrent(), comp);
}
Rotate(firstCut, middle, secondCut);
middle = firstCut.GetAdvanced(middle.Distance(secondCut));
InplaceMerge(first, firstCut, middle, comp);
InplaceMerge(middle, secondCut, last, comp);
}