pragma solidity ^0.5.0;

library SafeMath {
  
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        uint256 c = a - b;

        return c;
    }
    
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        uint256 c = a / b;
        return c;
    }
   
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0, "SafeMath: modulo by zero");
        return a % b;
    }
}

library Address {
  
    function isContract(address account) internal view returns (bool) {
     
        uint256 size;
        
        assembly { size := extcodesize(account) }
        return size > 0;
    }
}

interface IERC1820Registry {
   
    function setManager(address account, address newManager) external;
  
    function getManager(address account) external view returns (address);
 
    function setInterfaceImplementer(address account, bytes32 interfaceHash, address implementer) external;
  
    function getInterfaceImplementer(address account, bytes32 interfaceHash) external view returns (address);
   
    function interfaceHash(string calldata interfaceName) external pure returns (bytes32);
   
    function updateERC165Cache(address account, bytes4 interfaceId) external;

    function implementsERC165Interface(address account, bytes4 interfaceId) external view returns (bool);

    function implementsERC165InterfaceNoCache(address account, bytes4 interfaceId) external view returns (bool);

    event InterfaceImplementerSet(address indexed account, bytes32 indexed interfaceHash, address indexed implementer);

    event ManagerChanged(address indexed account, address indexed newManager);
}

interface IERC777 {
    
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);
   
    function granularity() external view returns (uint256);

    function totalSupply() external view returns (uint256);

    function balanceOf(address owner) external view returns (uint256);
  
    function send(address recipient, uint256 amount, bytes calldata data) external;
   
    function burn(uint256 amount, bytes calldata data) external;
   
    function isOperatorFor(address operator, address tokenHolder) external view returns (bool);
   
    function authorizeOperator(address operator) external;
    
    function revokeOperator(address operator) external;

    function defaultOperators() external view returns (address[] memory);

    
    function operatorSend(
        address sender,
        address recipient,
        uint256 amount,
        bytes calldata data,
        bytes calldata operatorData
    ) external;

    function operatorBurn(
        address account,
        uint256 amount,
        bytes calldata data,
        bytes calldata operatorData
    ) external;

    event Sent(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256 amount,
        bytes data,
        bytes operatorData
    );

    event Minted(address indexed operator, address indexed to, uint256 amount, bytes data, bytes operatorData);

    event Burned(address indexed operator, address indexed from, uint256 amount, bytes data, bytes operatorData);

    event AuthorizedOperator(address indexed operator, address indexed tokenHolder);

    event RevokedOperator(address indexed operator, address indexed tokenHolder);
}

interface IERC777Recipient {
    
    function tokensReceived(
        address operator,
        address from,
        address to,
        uint amount,
        bytes calldata userData,
        bytes calldata operatorData
    ) external;
}

interface IERC777Sender {
   
    function tokensToSend(
        address operator,
        address from,
        address to,
        uint amount,
        bytes calldata userData,
        bytes calldata operatorData
    ) external;
}

interface IERC20 {
    
    function totalSupply() external view returns (uint256);

    function balanceOf(address account) external view returns (uint256);

    function transfer(address recipient, uint256 amount) external returns (bool);

    function allowance(address owner, address spender) external view returns (uint256);

    function approve(address spender, uint256 amount) external returns (bool);

    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
  
    event Transfer(address indexed from, address indexed to, uint256 value);

    event Approval(address indexed owner, address indexed spender, uint256 value);
}

contract ERC777 is IERC777, IERC20 {
    using SafeMath for uint256;
    using Address for address;

    IERC1820Registry private _erc1820 = IERC1820Registry(0xc0cE3461c92D95b4E1D3ABeb5c9D378b1e418030);

    mapping(address => uint256) private _balances;

    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    bytes32 constant private senderHash    = 0x29ddb589b1fb5fc7cf394961c1adf5f8c6454761adf795e67fe149f658abe895;
    bytes32 constant private recipientHash = 0xb281fc8c12954d22544db45de3159a39272895b169a852b314f9cc762e44c53b;

    address[] private _defaultOperatorsArray;

    mapping(address => bool) private _defaultOperators;
    mapping(address => mapping(address => bool)) private _operators;
    mapping(address => mapping(address => bool)) private _revokedDefaultOperators;
    mapping (address => mapping (address => uint256)) private _allowances;

     constructor(
        string memory name,
        string memory symbol,
        address[] memory defaultOperators
    ) public {
        _name   = name;
        _symbol = symbol;

        _defaultOperatorsArray = defaultOperators;
        for (uint256 i = 0; i < _defaultOperatorsArray.length; i++) {
            _defaultOperators[_defaultOperatorsArray[i]] = true;
        }
        _erc1820.setInterfaceImplementer(address(this), keccak256("ERC777Token"), address(this));
        _erc1820.setInterfaceImplementer(address(this), keccak256("ERC20Token"), address(this));
    }


    function name() public view returns (string memory) {
        return _name;
    }
   function symbol() public view returns (string memory) {
        return _symbol;
    }
    function decimals() public pure returns (uint8) {
        return 18;
    }

    function granularity() public view returns (uint256) {
        return 18;
    }

    function totalSupply() public view returns (uint256) {
        return _totalSupply;
    }
 function balanceOf(address tokenHolder) public view returns (uint256) {
        return _balances[tokenHolder];
    }
    function send(address recipient, uint256 amount, bytes calldata data) external {
        _send(msg.sender, msg.sender, recipient, amount, data, "", true);
    }
    function transfer(address recipient, uint256 amount) external returns (bool) {
        require(recipient != address(0), "ERC777: transfer to the zero address");

        address from = msg.sender;

        _callTokensToSend(from, from, recipient, amount, "", "");

        _move(from, from, recipient, amount, "", "");

        _callTokensReceived(from, from, recipient, amount, "", "", false);

        return true;
    }

     function burn(uint256 amount, bytes calldata data) external {
        _burn(msg.sender, msg.sender, amount, data, "");
    }
    
    function isOperatorFor(
        address operator,
        address tokenHolder
    ) public view returns (bool) {
        return operator == tokenHolder ||
            (_defaultOperators[operator] && !_revokedDefaultOperators[tokenHolder][operator]) ||
            _operators[tokenHolder][operator];
    }
   function authorizeOperator(address operator) external {
        require(msg.sender != operator, "ERC777: authorizing self as operator");

        if (_defaultOperators[operator]) {
            delete _revokedDefaultOperators[msg.sender][operator];
        } else {
            _operators[msg.sender][operator] = true;
        }

        emit AuthorizedOperator(operator, msg.sender);
    }

     function revokeOperator(address operator) external {
        require(operator != msg.sender, "ERC777: revoking self as operator");

        if (_defaultOperators[operator]) {
            _revokedDefaultOperators[msg.sender][operator] = true;
        } else {
            delete _operators[msg.sender][operator];
        }

        emit RevokedOperator(operator, msg.sender);
    }

   function defaultOperators() public view returns (address[] memory) {
        return _defaultOperatorsArray;
    }

   function operatorSend(
        address sender,
        address recipient,
        uint256 amount,
        bytes calldata data,
        bytes calldata operatorData
    )
    external
    {
        require(isOperatorFor(msg.sender, sender), "ERC777: caller is not an operator for holder");
        _send(msg.sender, sender, recipient, amount, data, operatorData, true);
    }

  
    function operatorBurn(address account, uint256 amount, bytes calldata data, bytes calldata operatorData) external {
        require(isOperatorFor(msg.sender, account), "ERC777: caller is not an operator for holder");
        _burn(msg.sender, account, amount, data, operatorData);
    }


    function allowance(address holder, address spender) public view returns (uint256) {
        return _allowances[holder][spender];
    }


    function approve(address spender, uint256 value) external returns (bool) {
        address holder = msg.sender;
        _approve(holder, spender, value);
        return true;
    }

  
    function transferFrom(address holder, address recipient, uint256 amount) external returns (bool) {
        require(recipient != address(0), "ERC777: transfer to the zero address");
        require(holder != address(0), "ERC777: transfer from the zero address");

        address spender = msg.sender;

        _callTokensToSend(spender, holder, recipient, amount, "", "");

        _move(spender, holder, recipient, amount, "", "");
        _approve(holder, spender, _allowances[holder][spender].sub(amount));

        _callTokensReceived(spender, holder, recipient, amount, "", "", false);

        return true;
    }

    function _mint(
        address operator,
        address account,
        uint256 amount,
        bytes memory userData,
        bytes memory operatorData
    )
    internal
    {
        require(account != address(0), "ERC777: mint to the zero address");

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);

        _callTokensReceived(operator, address(0), account, amount, userData, operatorData, true);

        emit Minted(operator, account, amount, userData, operatorData);
        emit Transfer(address(0), account, amount);
    }

    function _send(
        address operator,
        address from,
        address to,
        uint256 amount,
        bytes memory userData,
        bytes memory operatorData,
        bool requireReceptionAck
    )
        private
    {
        require(from != address(0), "ERC777: send from the zero address");
        require(to != address(0), "ERC777: send to the zero address");

        _callTokensToSend(operator, from, to, amount, userData, operatorData);

        _move(operator, from, to, amount, userData, operatorData);

        _callTokensReceived(operator, from, to, amount, userData, operatorData, requireReceptionAck);
    }
    
    function _burn(
        address operator,
        address from,
        uint256 amount,
        bytes memory data,
        bytes memory operatorData
    )
        private
    {
        require(from != address(0), "ERC777: burn from the zero address");

        _callTokensToSend(operator, from, address(0), amount, data, operatorData);


        _totalSupply = _totalSupply.sub(amount);
        _balances[from] = _balances[from].sub(amount);

        emit Burned(operator, from, amount, data, operatorData);
        emit Transfer(from, address(0), amount);
    }

    function _move(
        address operator,
        address from,
        address to,
        uint256 amount,
        bytes memory userData,
        bytes memory operatorData
    )
        private
    {
        _balances[from] = _balances[from].sub(amount);
        _balances[to] = _balances[to].add(amount);

        emit Sent(operator, from, to, amount, userData, operatorData);
        emit Transfer(from, to, amount);
    }

    function _approve(address holder, address spender, uint256 value) private {
           require(spender != address(0), "ERC777: approve to the zero address");

        _allowances[holder][spender] = value;
        emit Approval(holder, spender, value);
    }

   function _callTokensToSend(
        address operator,
        address from,
        address to,
        uint256 amount,
        bytes memory userData,
        bytes memory operatorData
    )
        private
    {
        address implementer = _erc1820.getInterfaceImplementer(from, senderHash);
        if (implementer != address(0)) {
            IERC777Sender(implementer).tokensToSend(operator, from, to, amount, userData, operatorData);
        }
    }

     function _callTokensReceived(
        address operator,
        address from,
        address to,
        uint256 amount,
        bytes memory userData,
        bytes memory operatorData,
        bool requireReceptionAck
    )
        private
    {
        address implementer = _erc1820.getInterfaceImplementer(to, recipientHash);
        if (implementer != address(0)) {
            IERC777Recipient(implementer).tokensReceived(operator, from, to, amount, userData, operatorData);
        } else if (requireReceptionAck) {
            require(!to.isContract(), "ERC777: token recipient contract has no implementer for ERC777TokensRecipient");
        }
    }
}


//STARXtoken's smart contract
contract STARXtoken is ERC777 {
      constructor () public ERC777("STARX", "STARX", new address[](0)) {
        _mint(msg.sender, msg.sender, 1000000000 * 10 ** 18, "", "");
    }
}

{
  "compilationTarget": {
    "STARXtoken.sol": "STARXtoken"
  },
  "evmVersion": "byzantium",
  "libraries": {},
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}