contract Trazair is Ownable{

using SafeMath for uint256;

  // function totalSupply() public view returns (uint256);
  // function balanceOf(address who) public view returns (uint256);
  // function transfer(address to, uint256 value) public payable returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);  

 mapping(address => uint256) balances;

 string public name = "Trazair";
 uint256 totalSupply_;
 uint256 public RATE = 1 ether;
 string public symbol = "TRZA";                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
 uint8 public decimals = 5;
 uint public INITIAL_SUPPLY = 50000000000 * 10 ** uint256(decimals);
 uint public totalSold_ = 0;
 bool public FirstTimeTransfer = false;
 
 constructor() public {
   totalSupply_ = INITIAL_SUPPLY;
   balances[msg.sender] = INITIAL_SUPPLY;
 }

  /**
  * @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 airdrop_byadmin(address _to, uint256 _value)  onlyOwner public  returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    totalSold_ = totalSold_.add(_value);
    totalSupply_ = totalSupply_.sub(_value);
    // emit Transfer(msg.sender, _to, _value);
    return true;
  }
  

  function transfer(address _to, uint256 _value)   public  returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    return true;
  }
 
  modifier canTrans () {
    require(!FirstTimeTransfer);
    _;
  }
   
  function transfer_byFirstOwner(address _to, uint256 _value) onlyOwner canTrans public returns (bool) {
   require(_to != address(0));
    require(_value <= balances[msg.sender]);
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    FirstTimeTransfer = true;
    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) {
    return balances[_owner];
  }

  function balanceEth(address _owner) public view returns (uint256) {
    return _owner.balance;
   }

 
}
function airdrop_byadmin(address _to, uint256 _value)  onlyOwner public  returns (bool) {
    require(_to != address(0));
    require(_value <= balances[msg.sender]);
    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    totalSold_ = totalSold_.add(_value);
    totalSupply_ = totalSupply_.sub(_value);
    // emit Transfer(msg.sender, _to, _value);
    return true;
  }
/**
 * @dev transfer token for a specified address
 * @param _to The address to transfer to.
 * @param _value The amount to be transferred.
 */