pragma solidity ^0.4.20;
/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (a == 0) {
      return 0;
    }

    c = a * b;
    assert(c / a == b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  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 a / b;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
    c = a + b;
    assert(c >= a);
    return c;
  }
}
contract owned {
    address public owner;
    
    event Log(string s);
    
    constructor() public payable{
        owner = msg.sender;
    }

    modifier onlyOwner {
        require(msg.sender == owner);
        _;
    }
    function transferOwnership(address newOwner) onlyOwner public {
        owner = newOwner;
    }
    function isOwner()public{
        if(msg.sender==owner)emit Log("Owner");
        else{
            emit Log("Not Owner");
        }
    }
}
contract ERC20 is owned{
    using SafeMath for *;
    
    string public name;
    string public symbol;

    uint256 public totalSupply;
    uint8 public constant decimals = 4;

    mapping(address => uint256) balances;
    mapping(address => mapping (address => uint256)) allowed;
    
    event Transfer(address indexed from, address indexed to, uint tokens);
    event Approval(address indexed tokenOwner, address indexed spender, uint tokens);

    constructor(uint256 _totalSupply,string tokenName,string tokenSymbol) public {
        symbol = tokenSymbol;
        name = tokenName;
        totalSupply = _totalSupply;
        balances[owner] = totalSupply;
        emit Transfer(address(0), owner, totalSupply);
    }

    function totalSupply() public view returns (uint){
        return totalSupply;
    }

    function balanceOf(address tokenOwner) public view returns (uint balance) {
        return balances[tokenOwner];
    }

    function transfer(address to, uint tokens) public returns (bool success) {
        balances[msg.sender] = SafeMath.sub(balances[msg.sender ],tokens);
        balances[to] = SafeMath.add(balances[to], tokens);
        emit Transfer(msg.sender, to, tokens);
        return true;
    }

    function transferFrom(address from, address to, uint tokens) public returns (bool success) {
        balances[from] = SafeMath.sub(balances[from], tokens);
        allowed[from][msg.sender] = SafeMath.sub(allowed[from][msg.sender],(tokens));
        balances[to] = SafeMath.sub(balances[to],tokens);
        emit Transfer(from, to, tokens);
        return true;
    }

    function approve(address spender, uint tokens) public returns (bool success) {
        allowed[msg.sender][spender] = tokens;
        emit Approval(msg.sender, spender, tokens);
        return true;
    }

    function allowance(address tokenOwner, address spender) public view returns (uint remaining) {
        return allowed[tokenOwner][spender];
    }
}

contract NPLAY is ERC20 {
    
    uint256 activeUsers;

    mapping(address => bool) isRegistered;
    mapping(address => uint256) accountID;
    mapping(uint256 => address) accountFromID;
    mapping(address => bool) isTrusted;

    event Burn(address _from,uint256 _value);
    
    modifier isTrustedContract{
        require(isTrusted[msg.sender]);
        _;
    }
    
    modifier registered{
        require(isRegistered[msg.sender]);
        _;
    }
    
    constructor(
        string tokenName,
        string tokenSymbol) public payable
        ERC20(74145513585,tokenName,tokenSymbol)
    {
       
    }
    
    function distribute(address[] users,uint256[] balances) public onlyOwner {
         uint i;
        for(i = 0;i <users.length;i++){
            transferFrom(owner,users[i],balances[i]);
        }
    }

    function burnFrom(address _from, uint256 _value) internal returns (bool success) {
        require(_from == msg.sender || _from == owner);
        require(balances[_from] >= _value);
        balances[_from] = SafeMath.sub(balances[_from],_value);
        totalSupply = SafeMath.sub(totalSupply,_value);
        emit Burn(_from, _value);
        return true;
    }

    function contractBurn(address _for,uint256 value)external isTrustedContract{
        burnFrom(_for,value);
    }

    function burn(uint256 val)public{
        burnFrom(msg.sender,val);
    }

    function registerAccount(address user)internal{
        if(!isRegistered[user]){
            isRegistered[user] = true;
            activeUsers += 1;
            accountID[user] = activeUsers;
            accountFromID[activeUsers] = user;
        }
    }
    
    function registerExternal()external{
        registerAccount(msg.sender);
    }
    
    function register() public {
        registerAccount(msg.sender);
    }

    function testConnection() external {
        emit Log("CONNECTED");
    }
}