pragma solidity ^0.4.19;

contract Ownable {
  address public owner;

  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() public {
    owner = msg.sender;
  }

  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
   * @dev Allows the current owner to transfer control of the contract to a newOwner.
   * @param newOwner The address to transfer ownership to.
   */
  function transferOwnership(address newOwner) onlyOwner public {
    require(newOwner != address(0));      
    owner = newOwner;
  }
}

library AddressUtils {
  function isContract(address addr) internal view returns (bool) {
    uint256 size;
    assembly { size := extcodesize(addr) }
    return size > 0;
  }
}

interface ERC165ReceiverInterface {
  function tokensReceived(address _from, address _to, uint _amount, bytes _data) external returns (bool);
}

contract supportERC165Basic {
  bytes4 constant InvalidID = 0xffffffff;
  bytes4 constant ERC165ID = 0x01ffc9a7;
	
  function transfer_erc165(address to, uint256 value, bytes _data) public returns (bool);

  function doesContractImplementInterface(address _contract, bytes4 _interfaceId) internal view returns (bool) {
      uint256 success;
      uint256 result;

      (success, result) = noThrowCall(_contract, ERC165ID);
      if ((success==0)||(result==0)) {
          return false;
      }
  
      (success, result) = noThrowCall(_contract, InvalidID);
      if ((success==0)||(result!=0)) {
          return false;
      }

      (success, result) = noThrowCall(_contract, _interfaceId);
      if ((success==1)&&(result==1)) {
          return true;
      }
      return false;
  }

  function noThrowCall(address _contract, bytes4 _interfaceId) constant internal returns (uint256 success, uint256 result) {
      bytes4 erc165ID = ERC165ID;

      assembly {
              let x := mload(0x40)               // Find empty storage location using "free memory pointer"
              mstore(x, erc165ID)                // Place signature at begining of empty storage
              mstore(add(x, 0x04), _interfaceId) // Place first argument directly next to signature

              success := staticcall(
                                  30000,         // 30k gas
                                  _contract,     // To addr
                                  x,             // Inputs are stored at location x
                                  0x20,          // Inputs are 32 bytes long
                                  x,             // Store output over input (saves space)
                                  0x20)          // Outputs are 32 bytes long

              result := mload(x)                 // Load the result
      }
  }	
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

contract ERC20Basic is supportERC165Basic {
  function totalSupply() public view returns (uint256);
  function balanceOf(address who) public view returns (uint256);
  function transfer(address to, uint256 value) public returns (bool);
  event Transfer(address indexed from, address indexed to, uint256 value);
}

contract BasicToken is ERC20Basic {
  using SafeMath for uint256;
  using AddressUtils for address;

  mapping(address => uint256) balances;

  uint256 totalSupply_;

  /**
  * @dev total number of tokens in existence
  */
  function totalSupply() public view returns (uint256) {
    return totalSupply_;
  }

  /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
  function transfer(address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);

    // SafeMath.sub will throw if there is not enough balance.
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    Transfer(msg.sender, _to, _value);
  }
    
  /**
  * transfer with ERC165 interface
  **/
  function transfer_erc165(address _to, uint256 _value, bytes _data) public returns (bool) {
    transfer(_to, _value);
      
    if (!_to.isContract()) revert();
    
    ERC165ReceiverInterface i;
    if(!doesContractImplementInterface(_to, i.tokensReceived.selector)) revert(); 

    ERC165ReceiverInterface app= ERC165ReceiverInterface(_to);
    app.tokensReceived(msg.sender, _to, _value, _data);
    
    return true;
  }

  /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of.
  * @return An uint256 representing the amount owned by the passed address.
  */
  function balanceOf(address _owner) public view returns (uint256 balance) {
    return balances[_owner];
  }

}

library SafeMath {
  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return c;
  }

  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

contract ERC20 is ERC20Basic {
  function allowance(address owner, address spender) public view returns (uint256);
  function transferFrom(address from, address to, uint256 value) public returns (bool);
  function approve(address spender, uint256 value) public returns (bool);
  event Approval(address indexed owner, address indexed spender, uint256 value);
}

contract StandardToken is ERC20, BasicToken {

  mapping (address => mapping (address => uint256)) internal allowed;


  /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amount of tokens to be transferred
   */
  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
    require(_to != address(0));
    require(_value <= balances[_from]);
    require(_value <= allowed[_from][msg.sender]);

    balances[_from] = balances[_from].sub(_value);
    balances[_to] = balances[_to].add(_value);
    allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
    Transfer(_from, _to, _value);
    return true;
  }

  /**
   * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
   *
   * Beware that changing an allowance with this method brings the risk that someone may use both the old
   * and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
   * race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
   * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
   * @param _spender The address which will spend the funds.
   * @param _value The amount of tokens to be spent.
   */
  function approve(address _spender, uint256 _value) public returns (bool) {
    allowed[msg.sender][_spender] = _value;
    Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifying the amount of tokens still available for the spender.
   */
  function allowance(address _owner, address _spender) public view returns (uint256) {
    return allowed[_owner][_spender];
  }

  /**
   * @dev Increase the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To increment
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _addedValue The amount of tokens to increase the allowance by.
   */
  function increaseApproval(address _spender, uint _addedValue) public returns (bool) {
    allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

  /**
   * @dev Decrease the amount of tokens that an owner allowed to a spender.
   *
   * approve should be called when allowed[_spender] == 0. To decrement
   * allowed value is better to use this function to avoid 2 calls (and wait until
   * the first transaction is mined)
   * From MonolithDAO Token.sol
   * @param _spender The address which will spend the funds.
   * @param _subtractedValue The amount of tokens to decrease the allowance by.
   */
  function decreaseApproval(address _spender, uint _subtractedValue) public returns (bool) {
    uint oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}

contract RoboAiCoin is StandardToken, Ownable {

  string public name = "RoboAi Coin";
  string public symbol = "R2R";
  uint public decimals = 8;
    
  function RoboAiCoin() public {
    owner = msg.sender;
    totalSupply_ = 0;
    
    totalSupply_= 1 * 10 ** (9+8);  //1 Billion

    balances[owner] = totalSupply_;
	Transfer(address(0), owner, balances[owner]);
  }
}