pragma solidity ^0.4.19;

/**
 * @title ERC20
 * @dev ERC20 interface
 */
contract ERC20 {
    function balanceOf(address who) public constant returns (uint256);
    function transfer(address to, uint256 value) public returns (bool);
    function allowance(address owner, address spender) public constant returns (uint256);
    function transferFrom(address from, address to, uint256 value) public returns (bool);
    function approve(address spender, uint256 value) public returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
  address public owner;


  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() 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));
    emit OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
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;
  }
}

/**
 * The WPPToken contract does this and that...
 */
contract WPPToken is ERC20, Ownable {

	using SafeMath for uint256;

	uint256  public  totalSupply = 5000000000 * 1 ether;


	mapping  (address => uint256)             public          _balances;
    mapping  (address => mapping (address => uint256)) public  _approvals;

    string   public  name = "WPPTOKEN";
    string   public  symbol = "WPP";
    uint256  public  decimals = 18;

    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    

    constructor () public{
		_balances[owner] = totalSupply;
	}

    function totalSupply() public constant returns (uint256) {
        return totalSupply;
    }
    function balanceOf(address src) public constant returns (uint256) {
        return _balances[src];
    }
    function allowance(address src, address guy) public constant returns (uint256) {
        return _approvals[src][guy];
    }
    
    function transfer(address dst, uint256 wad) public returns (bool) {
        assert(_balances[msg.sender] >= wad);
        
        _balances[msg.sender] = _balances[msg.sender].sub(wad);
        _balances[dst] = _balances[dst].add(wad);
        
        emit Transfer(msg.sender, dst, wad);
        
        return true;
    }
    
    function transferFrom(address src, address dst, uint256 wad) public returns (bool) {
        assert(_balances[src] >= wad);
        assert(_approvals[src][msg.sender] >= wad);
        
        _approvals[src][msg.sender] = _approvals[src][msg.sender].sub(wad);
        _balances[src] = _balances[src].sub(wad);
        _balances[dst] = _balances[dst].add(wad);
        
        emit Transfer(src, dst, wad);
        
        return true;
    }
    
    function approve(address guy, uint256 wad) public returns (bool) {
        _approvals[msg.sender][guy] = wad;
        
        emit Approval(msg.sender, guy, wad);
        
        return true;
    }

}