/// <summary>
/// Same as Combin, contains additional user-defined parameter that will be passed to the delegate.
/// </summary>
// Code is copied from non-generic Combin. Code reuse decreases performace by 10%.
public static void Combin <ParamT>(DeckDescriptor deckDescr, int count, CardSet sharedCards, CardSet deadCards, EnumerateActionDelegate <ParamT> action, ParamT param)
{
UInt64 deadMask = deadCards.bits | sharedCards.bits;
UInt64 *pLiveCardMasks = stackalloc UInt64[deckDescr.Size];
int liveCardsCount = 0;
for (int c = 0; c < deckDescr.Size; ++c)
{
UInt64 bits = deckDescr.CardSets[c].bits;
if ((bits & deadMask) == 0)
{
pLiveCardMasks[liveCardsCount++] = bits;
}
}
CombinInternal(sharedCards.bits, pLiveCardMasks, liveCardsCount, count, action, param);
}
private static void CombinInternal <ParamT>(ulong m0, ulong *pLiveCardMasks, int liveCardsCount, int count, EnumerateActionDelegate <ParamT> action, ParamT param)
{
ulong m1;
ulong m2;
ulong m3;
ulong m4;
CardSet result;
// Alogritm for liveCardsCount = 10, count = 3:
// Live Masks: 0 1 2 3 4 5 6 7 8 9
// 1st loop b -> e
// 2nd loop b -> e
// 3rd loop b -> e
switch (count)
{
case 0:
result.bits = m0;
action(ref result, param);
break;
case 1:
for (int c1 = 0; c1 < liveCardsCount; ++c1)
{
result.bits = m0 | pLiveCardMasks[c1];
action(ref result, param);
}
break;
case 2:
for (int c1 = 1; c1 < liveCardsCount; ++c1)
{
m1 = m0 | pLiveCardMasks[c1];
for (int c2 = 0; c2 < c1; ++c2)
{
result.bits = m1 | pLiveCardMasks[c2];
action(ref result, param);
}
}
break;
case 3:
for (int c1 = 2; c1 < liveCardsCount; ++c1)
{
m1 = m0 | pLiveCardMasks[c1];
for (int c2 = 1; c2 < c1; ++c2)
{
m2 = m1 | pLiveCardMasks[c2];
for (int c3 = 0; c3 < c2; ++c3)
{
result.bits = m2 | pLiveCardMasks[c3];
action(ref result, param);
}
}
}
break;
case 4:
for (int c1 = 3; c1 < liveCardsCount; ++c1)
{
m1 = m0 | pLiveCardMasks[c1];
for (int c2 = 2; c2 < c1; ++c2)
{
m2 = m1 | pLiveCardMasks[c2];
for (int c3 = 1; c3 < c2; ++c3)
{
m3 = m2 | pLiveCardMasks[c3];
for (int c4 = 0; c4 < c3; ++c4)
{
result.bits = m3 | pLiveCardMasks[c4];
action(ref result, param);
}
}
}
}
break;
case 5:
for (int c1 = 4; c1 < liveCardsCount; ++c1)
{
m1 = m0 | pLiveCardMasks[c1];
for (int c2 = 3; c2 < c1; ++c2)
{
m2 = m1 | pLiveCardMasks[c2];
for (int c3 = 2; c3 < c2; ++c3)
{
m3 = m2 | pLiveCardMasks[c3];
for (int c4 = 1; c4 < c3; ++c4)
{
m4 = m3 | pLiveCardMasks[c4];
for (int c5 = 0; c5 < c4; ++c5)
{
result.bits = m4 | pLiveCardMasks[c5];
action(ref result, param);
}
}
}
}
}
break;
default:
for (int c1 = count - 1; c1 < liveCardsCount; ++c1)
{
m1 = m0 | pLiveCardMasks[c1];
for (int c2 = count - 2; c2 < c1; ++c2)
{
m2 = m1 | pLiveCardMasks[c2];
for (int c3 = count - 3; c3 < c2; ++c3)
{
m3 = m2 | pLiveCardMasks[c3];
for (int c4 = count - 4; c4 < c3; ++c4)
{
m4 = m3 | pLiveCardMasks[c4];
for (int c5 = count - 5; c5 < c4; ++c5)
{
CombinInternal(m4 | pLiveCardMasks[c5], pLiveCardMasks, c5, count - 5, action, param);
}
}
}
}
}
break;
}
}
