/**
* Index a hand on every round. This is not more expensive than just indexing the last round.
*
* @param cards
* @param indices an array where the indices for every round will be saved to
* @return hands index on the last round
*/
public long indexAll(int[] cards, long[] indices)
{
if (rounds > 0)
{
HandIndexerState state = new HandIndexerState();
for (int i = 0; i < rounds; i++)
{
indices[i] = indexNextRound(state, cards);
}
return(indices[rounds - 1]);
}
return(0);
}
/**
* Incrementally index the next round.
*
* @param state
* @param cards the cards for the next round only!
* @return hand's index on the latest round
*/
public long indexNextRound(HandIndexerState state, int[] cards)
{
int round = state.round++;
int[] ranks = new int[SUITS];
int[] shiftedRanks = new int[SUITS];
for (int i = 0, j = roundStart[round]; i < cardsPerRound[round]; ++i, ++j)
{
int rank = cards[j] >> 2, suit = cards[j] & 3, rankBit = 1 << rank;
ranks[suit] |= rankBit;
shiftedRanks[suit] |= (rankBit >> BitOperations.PopCount((uint)((rankBit - 1) & state.usedRanks[suit])));
}
for (int i = 0; i < SUITS; ++i)
{
int usedSize = BitOperations.PopCount((uint)state.usedRanks[i]), thisSize = BitOperations.PopCount((uint)ranks[i]);
state.suitIndex[i] += state.suitMultiplier[i] * rankSetToIndex[shiftedRanks[i]];
state.suitMultiplier[i] *= nCrRanks[RANKS - usedSize, thisSize];
state.usedRanks[i] |= ranks[i];
}
for (int i = 0, remaining = cardsPerRound[round]; i < SUITS - 1; ++i)
{
int thisSize = BitOperations.PopCount((uint)(ranks[i]));
state.permutationIndex += state.permutationMultiplier * thisSize;
state.permutationMultiplier *= remaining + 1;
remaining -= thisSize;
}
int configuration = permutationToConfiguration[round][state.permutationIndex];
int piIndex = permutationToPi[round][state.permutationIndex];
int equalIndex = configurationToEqual[round][configuration];
long offset = configurationToOffset[round][configuration];
int[] pi = suitPermutations[piIndex];
int[] suitIndex = new int[SUITS], suitMultiplier = new int[SUITS];
for (int i = 0; i < SUITS; ++i)
{
suitIndex[i] = state.suitIndex[pi[i]];
suitMultiplier[i] = state.suitMultiplier[pi[i]];
}
long index = offset, multiplier = 1;
for (int i = 0; i < SUITS;)
{
long part, size;
if (i + 1 < SUITS && equal[equalIndex, i + 1])
{
if (i + 2 < SUITS && equal[equalIndex, i + 2])
{
if (i + 3 < SUITS && equal[equalIndex, i + 3])
{
Swap(suitIndex, i, i + 1);
Swap(suitIndex, i + 2, i + 3);
Swap(suitIndex, i, i + 2);
Swap(suitIndex, i + 1, i + 3);
Swap(suitIndex, i + 1, i + 2);
part = suitIndex[i]
+ nCrGroups[suitIndex[i + 1] + 1, 2]
+ nCrGroups[suitIndex[i + 2] + 2, 3]
+ nCrGroups[suitIndex[i + 3] + 3, 4];
size = nCrGroups[suitMultiplier[i] + 3, 4];
i += 4;
}
else
{
Swap(suitIndex, i, i + 1);
Swap(suitIndex, i, i + 2);
Swap(suitIndex, i + 1, i + 2);
part = suitIndex[i] + nCrGroups[suitIndex[i + 1] + 1, 2]
+ nCrGroups[suitIndex[i + 2] + 2, 3];
size = nCrGroups[suitMultiplier[i] + 2, 3];
i += 3;
}
}
else
{
Swap(suitIndex, i, i + 1);
part = suitIndex[i] + nCrGroups[suitIndex[i + 1] + 1, 2];
size = nCrGroups[suitMultiplier[i] + 1, 2];
i += 2;
}
}
else
{
part = suitIndex[i];
size = suitMultiplier[i];
i += 1;
}
index += multiplier * part;
multiplier *= size;
}
return(index);
}