0xBitcoin_Mint.md

The most important method for EIP918 is mint() for the token distribution and it is incorporated as follows for a SHA3 algorithm:

 uint challengeNumber = block.blockhash(block.number - 1);
 uint miningTarget = 2**224;
 uint epochCount = 0;

 function mint(uint256 nonce, bytes32 challenge_digest) public returns (bool success) { 
             
             bytes32 digest =  keccak256(challengeNumber, msg.sender, nonce);

             //the challenge digest must match the expected
             if (digest != challenge_digest) revert();

             //the digest must be smaller than the target
             if(uint256(digest) > miningTarget) revert(); 

             //only allow one reward for each unique proof of work
             bytes32 solution = solutionForChallenge[challengeNumber];
             solutionForChallenge[challengeNumber] = digest;
             if(solution != 0x0) revert();  
            
             //implement a custom method for number of tokens to reward for a mint
             uint rewardAmount = getMiningReward();
            
             //use safe math to add tokens to the miners account
             balances[msg.sender] = balances[msg.sender].add(rewardAmount);

             //set the challenge number to a 'random' new value so future blocks cannot be premined
             challengeNumber = block.blockhash(block.number - 1);
             
             //A method can be added here which adjusts the mining target in order to adjust difficulty
             //_adjustMiningTarget()
             
             //track the number of mints that have occured
             epochCount = epochCount.add(1);
             
             //fire an event
             Mint(msg.sender, rewardAmount, epochCount, challengeNumber );

             return true;

        }
        
        function getChallengeNumber() public constant returns (bytes32) {
        return challengeNumber;
        }
       
       function getMiningTarget() public constant returns (uint) {
         return miningTarget;
       }
       
       
       function getMiningReward() public constant returns (uint) {
         //Feel free to modify this integer 
         return 50 * 10**uint(decimals);
       }