DGW3

unsigned int static DarkGravityWave3(const CBlockIndex* pindexLast, const CBlockHeader *pblock) {

/* current difficulty formula, darkcoin - DarkGravity v3, written by Evan Duffield - evan@darkcoin.io */

const CBlockIndex *BlockLastSolved = pindexLast;

const CBlockIndex *BlockReading = pindexLast;

const CBlockHeader *BlockCreating = pblock;

BlockCreating = BlockCreating;

int64 nActualTimespan = 0;

int64 LastBlockTime = 0;

int64 PastBlocksMin = 24;

int64 PastBlocksMax = 24;

int64 CountBlocks = 0;

CBigNum PastDifficultyAverage;

CBigNum PastDifficultyAveragePrev;

if (BlockLastSolved == NULL || BlockLastSolved->nHeight == 0 || BlockLastSolved->nHeight < PastBlocksMin) {

return bnProofOfWorkLimit.GetCompact();

}

for (unsigned int i = 1; BlockReading && BlockReading->nHeight > 0; i++) {

if (PastBlocksMax > 0 && i > PastBlocksMax) { break; }

CountBlocks++;

if(CountBlocks <= PastBlocksMin) {

if (CountBlocks == 1) { PastDifficultyAverage.SetCompact(BlockReading->nBits); }

else { PastDifficultyAverage = ((PastDifficultyAveragePrev * CountBlocks)+(CBigNum().SetCompact(BlockReading->nBits))) / (CountBlocks+1); }

PastDifficultyAveragePrev = PastDifficultyAverage;

}

if(LastBlockTime > 0){

int64 Diff = (LastBlockTime - BlockReading->GetBlockTime());

nActualTimespan += Diff;

}

LastBlockTime = BlockReading->GetBlockTime();

if (BlockReading->pprev == NULL) { assert(BlockReading); break; }

BlockReading = BlockReading->pprev;

}

CBigNum bnNew(PastDifficultyAverage);

int64 nTargetTimespan = CountBlocks*nTargetSpacing;

if (nActualTimespan < nTargetTimespan/3)

nActualTimespan = nTargetTimespan/3;

if (nActualTimespan > nTargetTimespan*3)

nActualTimespan = nTargetTimespan*3;

// Retarget

bnNew *= nActualTimespan;

bnNew /= nTargetTimespan;

/// debug print

printf("DarkGravityWave3 RETARGET\n");

printf("nTargetTimespan = %"PRI64d" nActualTimespan = %"PRI64d"\n", nTargetTimespan, nActualTimespan);

printf("Before: %08x %s\n", pindexLast->nBits, CBigNum().SetCompact(pindexLast->nBits).getuint256().ToString().c_str());

printf("After: %08x %s\n", bnNew.GetCompact(), bnNew.getuint256().ToString().c_str());

if (bnNew > bnProofOfWorkLimit){

bnNew = bnProofOfWorkLimit;

}

return bnNew.GetCompact();

}