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unsigned int static DUAL_KGW3(const CBlockIndex* pindexLast, const Consensus::Params& params, const CBlockHeader *pblock) {
	// current difficulty formula, ERC3 - DUAL_KGW3, written by Christian Knoepke - apfelbaum@email.de
	// BitSend and Eropecoin Developer
    const CBlockIndex *BlockLastSolved = pindexLast;
    const CBlockIndex *BlockReading = pindexLast;
	bool kgwdebug=false;
    uint64_t PastBlocksMass = 0;
    int64_t PastRateActualSeconds = 0;
    int64_t PastRateTargetSeconds = 0;
    double PastRateAdjustmentRatio = double(1);
    arith_uint256 PastDifficultyAverage;
    arith_uint256 PastDifficultyAveragePrev;
    double EventHorizonDeviation;
    double EventHorizonDeviationFast;
    double EventHorizonDeviationSlow;
	//DUAL_KGW3 SETUP
	static const uint64_t Blocktime = 5 * 60; 
	static const unsigned int timeDaySeconds = 60 * 60 * 24;
    uint64_t pastSecondsMin = timeDaySeconds * 0.025;
    uint64_t pastSecondsMax = timeDaySeconds * 7;
    uint64_t PastBlocksMin = pastSecondsMin / Blocktime;
    uint64_t PastBlocksMax = pastSecondsMax / Blocktime;
	
	 const arith_uint256 bnPowLimit = UintToArith256(params.powLimit);
	
    if (BlockLastSolved == NULL || BlockLastSolved->nHeight == 0 || (uint64_t)BlockLastSolved->nHeight < PastBlocksMin) {  return bnPowLimit.GetCompact(); }

    for (unsigned int i = 1; BlockReading && BlockReading->nHeight > 0; i++) {
        if (PastBlocksMax > 0 && i > PastBlocksMax) { break; }
        PastBlocksMass++;
        PastDifficultyAverage.SetCompact(BlockReading->nBits);
        if (i > 1) {
            if(PastDifficultyAverage >= PastDifficultyAveragePrev)
                PastDifficultyAverage = ((PastDifficultyAverage - PastDifficultyAveragePrev) / i) + PastDifficultyAveragePrev;
            else
                PastDifficultyAverage = PastDifficultyAveragePrev - ((PastDifficultyAveragePrev - PastDifficultyAverage) / i);
        }
        PastDifficultyAveragePrev = PastDifficultyAverage;
        PastRateActualSeconds = BlockLastSolved->GetBlockTime() - BlockReading->GetBlockTime();
        PastRateTargetSeconds = Blocktime * PastBlocksMass;
        PastRateAdjustmentRatio = double(1);
        if (PastRateActualSeconds < 0) { PastRateActualSeconds = 0; }
        if (PastRateActualSeconds != 0 && PastRateTargetSeconds != 0) {
            PastRateAdjustmentRatio = double(PastRateTargetSeconds) / double(PastRateActualSeconds);
        }
        EventHorizonDeviation = 1 + (0.7084 * pow((double(PastBlocksMass)/double(72)), -1.228));  //28.2 and 144 possible
        EventHorizonDeviationFast = EventHorizonDeviation;
        EventHorizonDeviationSlow = 1 / EventHorizonDeviation;

        if (PastBlocksMass >= PastBlocksMin) {
                if ((PastRateAdjustmentRatio <= EventHorizonDeviationSlow) || (PastRateAdjustmentRatio >= EventHorizonDeviationFast))
                { assert(BlockReading); break; }
        }
        if (BlockReading->pprev == NULL) { assert(BlockReading); break; }
        BlockReading = BlockReading->pprev;
    }
	
	//KGW Original
    arith_uint256 kgw_dual1(PastDifficultyAverage);
	arith_uint256 kgw_dual2;
	kgw_dual2.SetCompact(pindexLast->nBits);
    if (PastRateActualSeconds != 0 && PastRateTargetSeconds != 0) {
         kgw_dual1 *= PastRateActualSeconds;
         kgw_dual1 /= PastRateTargetSeconds;
    }
	
	int64_t nActualTime1 = pindexLast->GetBlockTime() - pindexLast->pprev->GetBlockTime();
	int64_t nActualTimespanshort = nActualTime1;	
	
	// Retarget BTC Original ...not exactly

    if (nActualTime1 < Blocktime / 3)
        nActualTime1 = Blocktime / 3;
    if (nActualTime1 > Blocktime * 3)
        nActualTime1 = Blocktime * 3;
		
    kgw_dual2 *= nActualTime1;
    kgw_dual2 /= Blocktime;
	
	//Fusion from Retarget and Classic KGW3 (BitSend=)
	
	arith_uint256 bnNew;
	bnNew = ((kgw_dual2 + kgw_dual1)/2);
	// DUAL KGW3 increased rapidly the Diff if Blocktime to last block under Blocktime/6 sec.
	
	if(kgwdebug)LogPrintf("nActualTimespanshort = %d \n", nActualTimespanshort );
	if( nActualTimespanshort < Blocktime/6 )
		{
		if(kgwdebug)LogPrintf("Vordiff:%08x %s bnNew first  \n", bnNew.GetCompact(), bnNew.ToString().c_str());
		const int nLongShortNew1   = 85; const int nLongShortNew2   = 100;
		bnNew = bnNew * nLongShortNew1;	bnNew = bnNew / nLongShortNew2;	
		if(kgwdebug)LogPrintf("Erhöhte Diff:\n %08x %s bnNew second \n", bnNew.GetCompact(), bnNew.ToString().c_str() );
		}

	
	//BitBreak BitSend
	// Reduce difficulty if current block generation time has already exceeded maximum time limit.
	const int nLongTimeLimit   = 6 * 60 * 60; 
    if(kgwdebug)
	{		
	LogPrintf("Prediff %08x %s\n", bnNew.GetCompact(), bnNew.ToString().c_str());
	LogPrintf("Vordiff %d \n", nLongTimeLimit);
	LogPrintf(" %d Block", BlockReading->nHeight );
	}
	
	if ((pblock-> nTime - pindexLast->GetBlockTime()) > nLongTimeLimit)  //block.nTime 
	{
		bnNew = bnPowLimit*30;
       	if(kgwdebug)LogPrintf("<BSD> Maximum block time hit - cute diff %08x %s\n", bnNew.GetCompact(), bnNew.ToString().c_str()); 
	}

    if (bnNew > bnPowLimit) {
        bnNew = bnPowLimit;
    }
    return bnNew.GetCompact();
}