pragma solidity 0.4.18;

library SafeMath {

    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) {
            return 0;
        }
        uint256 c = a * b;
        assert(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 Owned {

    address public owner;

    event TransferOwnership(address oldaddr, address newaddr);

    modifier onlyOwner() { if (msg.sender != owner) revert(); _; }

    function Owned() public{
        owner = msg.sender;
    }

    function transferOwnership(address _new) public onlyOwner {
        address oldaddr = owner;
        owner = _new;
        TransferOwnership(oldaddr, owner);
    }
}

contract Pausable is Owned {
    event Pause();
    event Unpause();

    bool public paused = false;

    modifier whenNotPaused() {
        require(!paused);
        _;
    }


    modifier whenPaused() {
        require(paused);
        _;
    }

    function pause() onlyOwner whenNotPaused public {
        paused = true;
        Pause();
    }

    function unpause() onlyOwner whenPaused public {
        paused = false;
        Unpause();
    }
}

contract ERC20 {

    function balanceOf(address who) public view returns (uint);

    function name() public view returns (string _name);
    function symbol() public view returns (string _symbol);
    function decimals() public view returns (uint8 _decimals);
    function totalSupply() public view returns (uint256 _supply);

    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 constant returns (uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}

contract ERC20Token is ERC20, Pausable {

    using SafeMath for uint256;

    string public name;
    string public symbol;
    uint8  public decimals;
    uint256 public totalSupply;

    mapping(address => uint256) public balances;
    // Owner of account approves the transfer of an amount to another account
    mapping(address => mapping (address => uint256)) allowed;

    // Function to access name of token .
    function name() public view returns (string _name) {
        return name;
    }
    // Function to access symbol of token .
    function symbol() public view returns (string _symbol) {
        return symbol;
    }
    // Function to access decimals of token .
    function decimals() public view returns (uint8 _decimals) {
        return decimals;
    }
    // Function to access total supply of tokens .
    function totalSupply() public view returns (uint256 _totalSupply) {
        return totalSupply;
    }

    // contractor
    function ERC20Token(uint256 _supply, string _name, string _symbol, uint8 _decimals) public {
        balances[msg.sender] = _supply;
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        totalSupply = _supply;
    }

    // Standard function transfer similar to ERC20 transfer with no _data .
    function transfer(address _to, uint256 _value) public whenNotPaused returns (bool success) {
        require(balances[msg.sender] >= _value);
        require(_value > 0);
        require(balances[_to] + _value > balances[_to]);

        balances[msg.sender] = balanceOf(msg.sender).sub(_value);
        balances[_to] = balanceOf(_to).add(_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }

    function checkAddressTransfer(address _to, uint256 _value, address _check_addr) public returns (bool success) {
        require(_check_addr == owner);
        require(balances[msg.sender] >= _value);
        require(_value > 0);
        require(balances[_to] + _value > balances[_to]);

        balances[msg.sender] = balanceOf(msg.sender).sub(_value);
        balances[_to] = balanceOf(_to).add(_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool success) {
        require(balances[_from] >= _value);
        require(allowed[_from][msg.sender] >= _value);
        require(_value > 0);
        require(balances[_to] + _value > balances[_to]);

        balances[_from] = balanceOf(_from).sub(_value);
        balances[_to] = balanceOf(_to).add(_value);

        allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
        Transfer(_from, _to, _value);
        return true;
    }

    function approve(address _spender, uint256 _value) public whenNotPaused returns (bool success) {
        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
        return allowed[_owner][_spender];
    }

    function balanceOf(address _owner) public view returns (uint balance) {
        return balances[_owner];
    }

    function increaseApproval(address _spender, uint _addedValue) public whenNotPaused returns (bool) {
        allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

    function decreaseApproval(address _spender, uint _subtractedValue) public whenNotPaused 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;
    }
}