pragma solidity ^0.4.25;

/**


					.----------------.  .----------------.  .----------------.  .----------------. 
					| .--------------. || .--------------. || .--------------. || .--------------. |
					| |  ____  ____  | || |     ____     | || |   _____      | || |  ________    | |
					| | |_   ||   _| | || |   .'    `.   | || |  |_   _|     | || | |_   ___ `.  | |
					| |   | |__| |   | || |  /  .--.  \  | || |    | |       | || |   | |   `. \ | |
					| |   |  __  |   | || |  | |    | |  | || |    | |   _   | || |   | |    | | | |
					| |  _| |  | |_  | || |  \  `--'  /  | || |   _| |__/ |  | || |  _| |___.' / | |
					| | |____||____| | || |   `.____.'   | || |  |________|  | || | |________.'  | |
					| |              | || |              | || |              | || |              | |
					| '--------------' || '--------------' || '--------------' || '--------------' |
					'----------------'  '----------------'  '----------------'  '----------------' 

*/

	/*==============================
    =          Version 7.7         =
    ==============================*/
	
contract EthereumSmartContract {    
    address EthereumNodes; 
	
    constructor() public { 
        EthereumNodes = msg.sender;
    }
    modifier restricted() {
        require(msg.sender == EthereumNodes);
        _;
    } 
	
    function GetEthereumNodes() public view returns (address owner) { return EthereumNodes; }
}

contract ldoh is EthereumSmartContract {
	
	/*==============================
    =            EVENTS            =
    ==============================*/
	
	event onCashbackCode	(address indexed hodler, address cashbackcode);		
	event onAffiliateBonus	(address indexed hodler, address indexed tokenAddress, string tokenSymbol, uint256 amount, uint256 endtime);		
	event onHoldplatform	(address indexed hodler, address indexed tokenAddress, string tokenSymbol, uint256 amount, uint256 endtime);
	event onUnlocktoken		(address indexed hodler, address indexed tokenAddress, string tokenSymbol, uint256 amount, uint256 endtime);
	event onReceiveAirdrop(address indexed hodler, uint256 amount, uint256 datetime);	
	
	event onAddContractAddress(address indexed hodler, address indexed contracthodler, uint256 Currentprice, uint256 _maxcontribution, string _ContractSymbol, uint256 _PercentPermonth, uint256 _HodlingTime);	
	
	event onHoldplatformsetting(address indexed hodler, address indexed Tokenairdrop, uint256 HPM_status, uint256 HPM_divider, uint256 HPM_ratio, uint256 datetime);	
	event onHoldplatformdeposit(address indexed hodler, uint256 amount, uint256 newbalance, uint256 datetime);	
	event onHoldplatformwithdraw(address indexed hodler, uint256 amount, uint256 newbalance, uint256 datetime);	
		
	
	/*==============================
    =          VARIABLES           =
    ==============================*/   

	//-------o Affiliate = 12% o-------o Cashback = 16% o-------o Total Receive = 88% o-------o Without Cashback = 72% o-------o	
	
	// Struct Database

    struct Safe {
        uint256 id;						// 01 -- > Registration Number
        uint256 amount;					// 02 -- > Total amount of contribution to this transaction
        uint256 endtime;				// 03 -- > The Expiration Of A Hold Platform Based On Unix Time
        address user;					// 04 -- > The ETH address that you are using
        address tokenAddress;			// 05 -- > The Token Contract Address That You Are Using
		string  tokenSymbol;			// 06 -- > The Token Symbol That You Are Using
		uint256 amountbalance; 			// 07 -- > 88% from Contribution / 72% Without Cashback
		uint256 cashbackbalance; 		// 08 -- > 16% from Contribution / 0% Without Cashback
		uint256 lasttime; 				// 09 -- > The Last Time You Withdraw Based On Unix Time
		uint256 percentage; 			// 10 -- > The percentage of tokens that are unlocked every month ( Default = 3% )
		uint256 percentagereceive; 		// 11 -- > The Percentage You Have Received
		uint256 tokenreceive; 			// 12 -- > The Number Of Tokens You Have Received
		uint256 lastwithdraw; 			// 13 -- > The Last Amount You Withdraw
		address referrer; 				// 14 -- > Your ETH referrer address
		bool 	cashbackstatus; 		// 15 -- > Cashback Status
    }
	
	uint256 private idnumber; 										// 01 -- > ID number ( Start from 500 )				
	uint256 public  TotalUser; 										// 02 -- > Total Smart Contract User				
		
	mapping(address => address) 		public cashbackcode; 		// 03 -- > Cashback Code 					
	mapping(address => uint256[]) 		public idaddress;			// 04 -- > Search Address by ID			
	mapping(address => address[]) 		public afflist;				// 05 -- > Affiliate List by ID					
	mapping(address => string) 			public ContractSymbol; 		// 06 -- > Contract Address Symbol				
	mapping(uint256 => Safe) 			private _safes; 			// 07 -- > Struct safe database	
	mapping(address => bool) 			public contractaddress; 	// 08 -- > Contract Address 	
	
	mapping(address => uint256) 		public percent; 			// 09 -- > Monthly Unlock Percentage (Default 3%)
	mapping(address => uint256) 		public hodlingTime; 		// 10 -- > Length of hold time in seconds
	mapping(address => uint256) 		public TokenBalance; 		// 11 -- > Token Balance							
	mapping(address => uint256) 		public maxcontribution; 	// 12 -- > Maximum Contribution					
	mapping(address => uint256) 		public AllContribution; 	// 13 -- > Deposit amount for all members		
	mapping(address => uint256) 		public AllPayments; 		// 14 -- > Withdraw amount for all members		
	mapping(address => uint256) 		public activeuser; 			// 15 -- > Active User Status
	
	mapping (address => mapping (uint256 => uint256)) 	public TXCount; 			
//2nd uint256, Category >>> 1 = Total User, 2 = Total TX Hold, 3 = Total TX Unlock, 4 = Total TX Airdrop, 5 = Total TX Affiliate Withdraw
	mapping (address => mapping (uint256 => uint256)) 	public token_price; 				
//2nd uint256, Category >>> 1 = Current Price, 2 = ATH Price, 3 = ATL Price				
	mapping (address => mapping (address => mapping (uint256 => uint256))) public Statistics;
//3rd uint256, Category >>> 1 = LifetimeContribution, 2 = LifetimePayments, 3 = Affiliatevault, 4 = Affiliateprofit, 5 = ActiveContribution
	
		// Airdrop - Hold Platform (HPM)
								
	address public Holdplatform_address;	
	uint256 public Holdplatform_balance; 	
	mapping(address => uint256) public Holdplatform_status;
	mapping(address => uint256) public Holdplatform_divider; 	
	
	/*==============================
    =          CONSTRUCTOR         =
    ==============================*/  	
   
    constructor() public {     	 	
        idnumber 				= 500;
		Holdplatform_address	= 0x23bAdee11Bf49c40669e9b09035f048e9146213e;	//Change before deploy
    }
    
	
	/*==============================
    =    AVAILABLE FOR EVERYONE    =
    ==============================*/  

//-------o Function 01 - Ethereum Payable

    function () public payable {  
		if (msg.value == 0) {
		
			for(uint256 i = 1; i < idnumber; i++) {            
				Safe storage s = _safes[i];
				if (s.user == msg.sender) {
				
					Unlocktoken(s.tokenAddress, s.id);
				}
			}
					
		} else { revert(); }
    }
	
//-------o Function 02 - Cashback Code

    function CashbackCode(address _cashbackcode) public {		
		require(_cashbackcode != msg.sender);		
		if (cashbackcode[msg.sender] == 0 && activeuser[_cashbackcode] >= 1) { 
		cashbackcode[msg.sender] = _cashbackcode; }
		else { cashbackcode[msg.sender] = EthereumNodes; }		
		
	emit onCashbackCode(msg.sender, _cashbackcode);		
    } 
	
//-------o Function 03 - Contribute 

	//--o 01
    function Holdplatform(address tokenAddress, uint256 amount) public {
        require(tokenAddress != 0x0);
		require(amount > 0 && add(Statistics[msg.sender][tokenAddress][5], amount) <= maxcontribution[tokenAddress] );
		
		if (contractaddress[tokenAddress] == false) { revert(); } else { 		
		ERC20Interface token 			= ERC20Interface(tokenAddress);       
        require(token.transferFrom(msg.sender, address(this), amount));	
		
		Airdrop(tokenAddress, amount, 1);  
		HodlTokens2(tokenAddress, amount);}							
	}
	
	//--o 02	
    function HodlTokens2(address ERC, uint256 amount) private {
		
		uint256 AvailableBalances 					= div(mul(amount, 72), 100);	
		
		if (cashbackcode[msg.sender] == 0 ) { //--o  Hold without cashback code
		
			address ref								= EthereumNodes;
			cashbackcode[msg.sender] 				= EthereumNodes;
			uint256 AvailableCashback 				= 0; 			
			uint256 zerocashback 					= div(mul(amount, 28), 100); 
			Statistics[EthereumNodes][ERC][3] 		= add(Statistics[EthereumNodes][ERC][3], zerocashback);
			Statistics[EthereumNodes][ERC][4]		= add(Statistics[EthereumNodes][ERC][4], zerocashback); 		
			
		} else { 	//--o  Cashback code has been activated
		
			ref										= cashbackcode[msg.sender];
			uint256 affcomission 					= div(mul(amount, 12), 100); 	
			AvailableCashback 						= div(mul(amount, 16), 100);			
			uint256 ReferrerContribution 			= Statistics[ref][ERC][5];		
			uint256 ReferralContribution			= add(Statistics[ref][ERC][5], amount);
			
			if (ReferrerContribution >= ReferralContribution) { //--o  if referrer contribution >= referral contribution
		
				Statistics[ref][ERC][3] 			= add(Statistics[ref][ERC][3], affcomission); 
				Statistics[ref][ERC][4] 			= add(Statistics[ref][ERC][4], affcomission); 	
				
			} else {											//--o  if referral contribution > referrer contribution
			
				uint256 Newbie 						= div(mul(ReferrerContribution, 12), 100); 			
				Statistics[ref][ERC][3]				= add(Statistics[ref][ERC][3], Newbie); 
				Statistics[ref][ERC][4] 			= add(Statistics[ref][ERC][4], Newbie); 
				
				uint256 NodeFunds 					= sub(affcomission, Newbie);	
				Statistics[EthereumNodes][ERC][3] 	= add(Statistics[EthereumNodes][ERC][3], NodeFunds);
				Statistics[EthereumNodes][ERC][4] 	= add(Statistics[EthereumNodes][ERC][4], NodeFunds); 				
			}
		} 

		HodlTokens3(ERC, amount, AvailableBalances, AvailableCashback, ref); 	
	}
	//--o 04	
    function HodlTokens3(address ERC, uint256 amount, uint256 AvailableBalances, uint256 AvailableCashback, address ref) private {
	    
	    ERC20Interface token 	= ERC20Interface(ERC); 	
		uint256 TokenPercent 	= percent[ERC];	
		uint256 TokenHodlTime 	= hodlingTime[ERC];	
		uint256 HodlTime		= add(now, TokenHodlTime);
		
		uint256 AM = amount; 	uint256 AB = AvailableBalances;		uint256 AC = AvailableCashback;	
		amount 	= 0; AvailableBalances = 0; AvailableCashback = 0;
		
		_safes[idnumber] = Safe(idnumber, AM, HodlTime, msg.sender, ERC, token.symbol(), AB, AC, now, TokenPercent, 0, 0, 0, ref, false);	
				
		Statistics[msg.sender][ERC][1]			= add(Statistics[msg.sender][ERC][1], AM); 
		Statistics[msg.sender][ERC][5]  		= add(Statistics[msg.sender][ERC][5], AM); 			
		AllContribution[ERC] 					= add(AllContribution[ERC], AM);   	
        TokenBalance[ERC] 						= add(TokenBalance[ERC], AM);  

		if(activeuser[msg.sender] == 1 ) {
        idaddress[msg.sender].push(idnumber); idnumber++; TXCount[ERC][2]++;  }		
		else { 
		afflist[ref].push(msg.sender); idaddress[msg.sender].push(idnumber); idnumber++; TXCount[ERC][1]++; TXCount[ERC][2]++; TotalUser++;   }
		
		activeuser[msg.sender] 					= 1;  	
		
        emit onHoldplatform(msg.sender, ERC, token.symbol(), AM, HodlTime);		
			
	}

//-------o Function 05 - Claim Token That Has Been Unlocked
    function Unlocktoken(address tokenAddress, uint256 id) public {
        require(tokenAddress != 0x0);
        require(id != 0);        
        
        Safe storage s = _safes[id];
        require(s.user == msg.sender);  
		require(s.tokenAddress == tokenAddress);
		
		if (s.amountbalance == 0) { revert(); } else { UnlockToken2(tokenAddress, id); }
    }
    //--o 01
    function UnlockToken2(address ERC, uint256 id) private {
        Safe storage s = _safes[id];      
        require(s.id != 0);
        require(s.tokenAddress == ERC);

        uint256 eventAmount				= s.amountbalance;
        address eventTokenAddress 		= s.tokenAddress;
        string memory eventTokenSymbol 	= s.tokenSymbol;		
		     
        if(s.endtime < now){ //--o  Hold Complete
        
		uint256 amounttransfer 					= add(s.amountbalance, s.cashbackbalance);
		Statistics[msg.sender][ERC][5] 			= sub(Statistics[s.user][s.tokenAddress][5], s.amount); 		
		s.lastwithdraw 							= s.amountbalance;   s.amountbalance = 0;   s.lasttime = now;  		
		PayToken(s.user, s.tokenAddress, amounttransfer); 
		
		    if(s.cashbackbalance > 0 && s.cashbackstatus == false || s.cashbackstatus == true) {
            s.tokenreceive 	= div(mul(s.amount, 88), 100) ; 	s.percentagereceive = mul(1000000000000000000, 88);
            }
			else {
			s.tokenreceive 	= div(mul(s.amount, 72), 100) ;     s.percentagereceive = mul(1000000000000000000, 72);
			}
			
		s.cashbackbalance = 0;	
		emit onUnlocktoken(msg.sender, eventTokenAddress, eventTokenSymbol, eventAmount, now);
		
        } else { UnlockToken3(ERC, s.id); }
        
    }   
	//--o 02
	function UnlockToken3(address ERC, uint256 id) private {		
		Safe storage s = _safes[id];
        
        require(s.id != 0);
        require(s.tokenAddress == ERC);		
			
		uint256 timeframe  			= sub(now, s.lasttime);			                            
		uint256 CalculateWithdraw 	= div(mul(div(mul(s.amount, s.percentage), 100), timeframe), 2592000); // 2592000 = seconds30days
							//--o   = s.amount * s.percentage / 100 * timeframe / seconds30days	;
		                         
		uint256 MaxWithdraw 		= div(s.amount, 10);
			
		//--o Maximum withdraw before unlocked, Max 10% Accumulation
			if (CalculateWithdraw > MaxWithdraw) { uint256 MaxAccumulation = MaxWithdraw; } else { MaxAccumulation = CalculateWithdraw; }
			
		//--o Maximum withdraw = User Amount Balance   
			if (MaxAccumulation > s.amountbalance) { uint256 realAmount1 = s.amountbalance; } else { realAmount1 = MaxAccumulation; }
			
		uint256 realAmount			= add(s.cashbackbalance, realAmount1); 			
		uint256 newamountbalance 	= sub(s.amountbalance, realAmount1);
		s.cashbackbalance 			= 0; 
		s.amountbalance 			= newamountbalance;
		s.lastwithdraw 				= realAmount; 
		s.lasttime 					= now; 		
			
		UnlockToken4(ERC, id, newamountbalance, realAmount);		
    }   
	//--o 03
    function UnlockToken4(address ERC, uint256 id, uint256 newamountbalance, uint256 realAmount) private {
        Safe storage s = _safes[id];
        
        require(s.id != 0);
        require(s.tokenAddress == ERC);

        uint256 eventAmount				= realAmount;
        address eventTokenAddress 		= s.tokenAddress;
        string memory eventTokenSymbol 	= s.tokenSymbol;		

		uint256 tokenaffiliate 		= div(mul(s.amount, 12), 100) ; 
		uint256 maxcashback 		= div(mul(s.amount, 16), 100) ;

		uint256 sid = s.id;
		
			if (cashbackcode[msg.sender] == EthereumNodes && idaddress[msg.sender][0] == sid ) {
			uint256 tokenreceived 	= sub(sub(sub(s.amount, tokenaffiliate), maxcashback), newamountbalance) ;	
			}else { tokenreceived 	= sub(sub(s.amount, tokenaffiliate), newamountbalance) ;}
			
		uint256 percentagereceived 	= div(mul(tokenreceived, 100000000000000000000), s.amount) ; 	
		
		s.tokenreceive 					= tokenreceived; 
		s.percentagereceive 			= percentagereceived; 		

		PayToken(s.user, s.tokenAddress, realAmount);           		
		emit onUnlocktoken(msg.sender, eventTokenAddress, eventTokenSymbol, eventAmount, now);
    } 
	//--o Pay Token
    function PayToken(address user, address tokenAddress, uint256 amount) private {
        
        ERC20Interface token = ERC20Interface(tokenAddress);        
        require(token.balanceOf(address(this)) >= amount);
        token.transfer(user, amount);
		
		TokenBalance[tokenAddress] 					= sub(TokenBalance[tokenAddress], amount); 
		AllPayments[tokenAddress] 					= add(AllPayments[tokenAddress], amount);
		Statistics[msg.sender][tokenAddress][2]  	= add(Statistics[user][tokenAddress][2], amount); 
		
		TXCount[tokenAddress][3]++;

		Airdrop(tokenAddress, amount, 4);   
	}
	
//-------o Function 05 - Airdrop

    function Airdrop(address tokenAddress, uint256 amount, uint256 extradivider) private {
		
		if (Holdplatform_status[tokenAddress] == 1) {
		require(Holdplatform_balance > 0 );
		
		uint256 divider 		= Holdplatform_divider[tokenAddress];
		uint256 airdrop			= div(div(amount, divider), extradivider);
		
		address airdropaddress	= Holdplatform_address;
		ERC20Interface token 	= ERC20Interface(airdropaddress);        
        token.transfer(msg.sender, airdrop);
		
		Holdplatform_balance	= sub(Holdplatform_balance, airdrop);
		TXCount[tokenAddress][4]++;
		
		emit onReceiveAirdrop(msg.sender, airdrop, now);
		}	
	}
	
//-------o Function 06 - Get How Many Contribute ?

    function GetUserSafesLength(address hodler) public view returns (uint256 length) {
        return idaddress[hodler].length;
    }
	
//-------o Function 07 - Get How Many Affiliate ?

    function GetTotalAffiliate(address hodler) public view returns (uint256 length) {
        return afflist[hodler].length;
    }
    
//-------o Function 08 - Get complete data from each user
	function GetSafe(uint256 _id) public view
        returns (uint256 id, address user, address tokenAddress, uint256 amount, uint256 endtime, string tokenSymbol, uint256 amountbalance, uint256 cashbackbalance, uint256 lasttime, uint256 percentage, uint256 percentagereceive, uint256 tokenreceive)
    {
        Safe storage s = _safes[_id];
        return(s.id, s.user, s.tokenAddress, s.amount, s.endtime, s.tokenSymbol, s.amountbalance, s.cashbackbalance, s.lasttime, s.percentage, s.percentagereceive, s.tokenreceive);
    }
	
//-------o Function 09 - Withdraw Affiliate Bonus

    function WithdrawAffiliate(address user, address tokenAddress) public {  
		require(tokenAddress != 0x0);		
		require(Statistics[user][tokenAddress][3] > 0 );
		
		uint256 amount = Statistics[msg.sender][tokenAddress][3];
		Statistics[msg.sender][tokenAddress][3] = 0;
		
		TokenBalance[tokenAddress] 		= sub(TokenBalance[tokenAddress], amount); 
		AllPayments[tokenAddress] 		= add(AllPayments[tokenAddress], amount);
		
		uint256 eventAmount				= amount;
        address eventTokenAddress 		= tokenAddress;
        string 	memory eventTokenSymbol = ContractSymbol[tokenAddress];	
        
        ERC20Interface token = ERC20Interface(tokenAddress);        
        require(token.balanceOf(address(this)) >= amount);
        token.transfer(user, amount);
		
		Statistics[user][tokenAddress][2] 	= add(Statistics[user][tokenAddress][2], amount);

		TXCount[tokenAddress][5]++;		
		
		emit onAffiliateBonus(msg.sender, eventTokenAddress, eventTokenSymbol, eventAmount, now);
		
		Airdrop(tokenAddress, amount, 4); 
    } 		
	
	
	/*==============================
    =          RESTRICTED          =
    ==============================*/  	

//-------o 01 Add Contract Address	
    function AddContractAddress(address tokenAddress, uint256 Currentprice, uint256 _maxcontribution, string _ContractSymbol, uint256 _PercentPermonth) public restricted {
		uint256 newSpeed	= _PercentPermonth;
		require(newSpeed >= 3 && newSpeed <= 12);
		
		percent[tokenAddress] 			= newSpeed;	
		ContractSymbol[tokenAddress] 	= _ContractSymbol;
		maxcontribution[tokenAddress] 	= _maxcontribution;	
		
		uint256 _HodlingTime 			= mul(div(72, newSpeed), 30);
		uint256 HodlTime 				= _HodlingTime * 1 days;		
		hodlingTime[tokenAddress] 		= HodlTime;	
		
		token_price[tokenAddress][1] 	= Currentprice;
		contractaddress[tokenAddress] 	= true;
		
		emit onAddContractAddress(msg.sender, tokenAddress, Currentprice, _maxcontribution, _ContractSymbol, _PercentPermonth, HodlTime);
    }
	
//-------o 02 - Update Token Price (USD)
	
	function TokenPrice(address tokenAddress, uint256 Currentprice, uint256 ATHprice, uint256 ATLprice) public restricted  {
		
		if (Currentprice > 0  ) { token_price[tokenAddress][1] = Currentprice; }
		if (ATHprice > 0  ) { token_price[tokenAddress][2] = ATHprice; }
		if (ATLprice > 0  ) { token_price[tokenAddress][3] = ATLprice; }

    }
	
//-------o 03 Hold Platform
    function Holdplatform_Airdrop(address tokenAddress, uint256 HPM_status, uint256 HPM_divider) public restricted {
		require(HPM_status == 0 || HPM_status == 1 );
		
		Holdplatform_status[tokenAddress] 	= HPM_status;	
		Holdplatform_divider[tokenAddress] 	= HPM_divider;	// Airdrop = 100% : Divider
		uint256 HPM_ratio					= div(100, HPM_divider);
		
		emit onHoldplatformsetting(msg.sender, tokenAddress, HPM_status, HPM_divider, HPM_ratio, now);
	
    }	
	//--o Deposit
	function Holdplatform_Deposit(uint256 amount) restricted public {
		require(amount > 0 );
        
       	ERC20Interface token = ERC20Interface(Holdplatform_address);       
        require(token.transferFrom(msg.sender, address(this), amount));
		
		uint256 newbalance		= add(Holdplatform_balance, amount) ;
		Holdplatform_balance 	= newbalance;
		
		emit onHoldplatformdeposit(msg.sender, amount, newbalance, now);
    }
	//--o Withdraw
	function Holdplatform_Withdraw(uint256 amount) restricted public {
        require(Holdplatform_balance > 0);
        
		uint256 newbalance		= sub(Holdplatform_balance, amount) ;
		Holdplatform_balance 	= newbalance;
        
        ERC20Interface token = ERC20Interface(Holdplatform_address);
        
        require(token.balanceOf(address(this)) >= amount);
        token.transfer(msg.sender, amount);
		
		emit onHoldplatformwithdraw(msg.sender, amount, newbalance, now);
    }
	
//-------o 04 - Return All Tokens To Their Respective Addresses    
    function ReturnAllTokens() restricted public
    {

        for(uint256 i = 1; i < idnumber; i++) {            
            Safe storage s = _safes[i];
            if (s.id != 0) {
				
				if(s.amountbalance > 0) {
					uint256 amount = add(s.amountbalance, s.cashbackbalance);
					PayToken(s.user, s.tokenAddress, amount);
					s.amountbalance							= 0;
					s.cashbackbalance						= 0;
					Statistics[s.user][s.tokenAddress][5]	= 0;
				}
            }
        }
    }   
	
	
	/*==============================
    =      SAFE MATH FUNCTIONS     =
    ==============================*/  	
	
	function mul(uint256 a, uint256 b) internal pure returns (uint256) {
		if (a == 0) {
			return 0;
		}
		uint256 c = a * b; 
		require(c / a == b);
		return c;
	}
	
	function div(uint256 a, uint256 b) internal pure returns (uint256) {
		require(b > 0); 
		uint256 c = a / b;
		return c;
	}
	
	function sub(uint256 a, uint256 b) internal pure returns (uint256) {
		require(b <= a);
		uint256 c = a - b;
		return c;
	}
	
	function add(uint256 a, uint256 b) internal pure returns (uint256) {
		uint256 c = a + b;
		require(c >= a);
		return c;
	}
    
}


	/*==============================
    =        ERC20 Interface       =
    ==============================*/ 

contract ERC20Interface {

    uint256 public totalSupply;
    uint256 public decimals;
    
    function symbol() public view returns (string);
    function balanceOf(address _owner) public view returns (uint256 balance);
    function transfer(address _to, uint256 _value) public returns (bool success);
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success);
    function approve(address _spender, uint256 _value) public returns (bool success);
    function allowance(address _owner, address _spender) public view returns (uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value); 
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}