// Vulnerability label: clean
pragma solidity 0.4.24;









/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * See https://github.com/ethereum/EIPs/issues/179
 */
contract ERC20Basic {
  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);
}




/**
 * @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;
  }
}



/**
 * @title Basic token
 * @dev Basic version of StandardToken, with no allowances.
 */
contract BasicToken is ERC20Basic {
  using SafeMath for uint256;

  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]);

    balances[msg.sender] = balances[msg.sender].sub(_value);
    balances[_to] = balances[_to].add(_value);
    emit Transfer(msg.sender, _to, _value);
    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];
  }

}






/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
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
  );
}



/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * https://github.com/ethereum/EIPs/issues/20
 * Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 */
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);
    emit 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;
    emit 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,
    uint256 _addedValue
  )
    public
    returns (bool)
  {
    allowed[msg.sender][_spender] = (
      allowed[msg.sender][_spender].add(_addedValue));
    emit 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,
    uint256 _subtractedValue
  )
    public
    returns (bool)
  {
    uint256 oldValue = allowed[msg.sender][_spender];
    if (_subtractedValue > oldValue) {
      allowed[msg.sender][_spender] = 0;
    } else {
      allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
    }
    emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
    return true;
  }

}








/**
 * @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 OwnershipRenounced(address indexed previousOwner);
  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 relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @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) public onlyOwner {
    _transferOwnership(_newOwner);
  }

  /**
   * @dev Transfers control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function _transferOwnership(address _newOwner) internal {
    require(_newOwner != address(0));
    emit OwnershipTransferred(owner, _newOwner);
    owner = _newOwner;
  }
}



/**
 * @title Contracts that should not own Ether
 * @author Remco Bloemen <remco@2π.com>
 * @dev This tries to block incoming ether to prevent accidental loss of Ether. Should Ether end up
 * in the contract, it will allow the owner to reclaim this ether.
 * @notice Ether can still be sent to this contract by:
 * calling functions labeled `payable`
 * `selfdestruct(contract_address)`
 * mining directly to the contract address
 */
contract HasNoEther is Ownable {

  /**
  * @dev Constructor that rejects incoming Ether
  * The `payable` flag is added so we can access `msg.value` without compiler warning. If we
  * leave out payable, then Solidity will allow inheriting contracts to implement a payable
  * constructor. By doing it this way we prevent a payable constructor from working. Alternatively
  * we could use assembly to access msg.value.
  */
  constructor() public payable {
    require(msg.value == 0);
  }

  /**
   * @dev Disallows direct send by settings a default function without the `payable` flag.
   */
  function() external {
  }

  /**
   * @dev Transfer all Ether held by the contract to the owner.
   */
  function reclaimEther() external onlyOwner {
    owner.transfer(address(this).balance);
  }
}













/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure.
 * To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
  function safeTransfer(ERC20Basic token, address to, uint256 value) internal {
    require(token.transfer(to, value));
  }

  function safeTransferFrom(
    ERC20 token,
    address from,
    address to,
    uint256 value
  )
    internal
  {
    require(token.transferFrom(from, to, value));
  }

  function safeApprove(ERC20 token, address spender, uint256 value) internal {
    require(token.approve(spender, value));
  }
}



/**
 * @title Contracts that should be able to recover tokens
 * @author SylTi
 * @dev This allow a contract to recover any ERC20 token received in a contract by transferring the balance to the contract owner.
 * This will prevent any accidental loss of tokens.
 */
contract CanReclaimToken is Ownable {
  using SafeERC20 for ERC20Basic;

  /**
   * @dev Reclaim all ERC20Basic compatible tokens
   * @param token ERC20Basic The address of the token contract
   */
  function reclaimToken(ERC20Basic token) external onlyOwner {
    uint256 balance = token.balanceOf(this);
    token.safeTransfer(owner, balance);
  }

}



/**
 * @title Contracts that should not own Tokens
 * @author Remco Bloemen <remco@2π.com>
 * @dev This blocks incoming ERC223 tokens to prevent accidental loss of tokens.
 * Should tokens (any ERC20Basic compatible) end up in the contract, it allows the
 * owner to reclaim the tokens.
 */
contract HasNoTokens is CanReclaimToken {

 /**
  * @dev Reject all ERC223 compatible tokens
  * @param from_ address The address that is transferring the tokens
  * @param value_ uint256 the amount of the specified token
  * @param data_ Bytes The data passed from the caller.
  */
  function tokenFallback(address from_, uint256 value_, bytes data_) external {
    from_;
    value_;
    data_;
    revert();
  }

}






/**
 * @title Contracts that should not own Contracts
 * @author Remco Bloemen <remco@2π.com>
 * @dev Should contracts (anything Ownable) end up being owned by this contract, it allows the owner
 * of this contract to reclaim ownership of the contracts.
 */
contract HasNoContracts is Ownable {

  /**
   * @dev Reclaim ownership of Ownable contracts
   * @param contractAddr The address of the Ownable to be reclaimed.
   */
  function reclaimContract(address contractAddr) external onlyOwner {
    Ownable contractInst = Ownable(contractAddr);
    contractInst.transferOwnership(owner);
  }
}



/**
 * @title Base contract for contracts that should not own things.
 * @author Remco Bloemen <remco@2π.com>
 * @dev Solves a class of errors where a contract accidentally becomes owner of Ether, Tokens or
 * Owned contracts. See respective base contracts for details.
 */
contract NoOwner is HasNoEther, HasNoTokens, HasNoContracts {
}






/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
contract BurnableToken is BasicToken {

  event Burn(address indexed burner, uint256 value);

  /**
   * @dev Burns a specific amount of tokens.
   * @param _value The amount of token to be burned.
   */
  function burn(uint256 _value) public {
    _burn(msg.sender, _value);
  }

  function _burn(address _who, uint256 _value) internal {
    require(_value <= balances[_who]);
    // no need to require value <= totalSupply, since that would imply the
    // sender's balance is greater than the totalSupply, which *should* be an assertion failure

    balances[_who] = balances[_who].sub(_value);
    totalSupply_ = totalSupply_.sub(_value);
    emit Burn(_who, _value);
    emit Transfer(_who, address(0), _value);
  }
}




/*
Copyright 2018 Vibeo

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
 */





contract CustomWhitelist is Ownable {
  mapping(address => bool) public whitelist;
  uint256 public numberOfWhitelists;

  event WhitelistedAddressAdded(address _addr);
  event WhitelistedAddressRemoved(address _addr);

  /**
   * @dev Throws if called by any account that's not whitelisted.
   */
  modifier onlyWhitelisted() {
    require(whitelist[msg.sender] || msg.sender == owner);
    _;
  }

  constructor() public {
    whitelist[msg.sender] = true;
    numberOfWhitelists = 1;
    emit WhitelistedAddressAdded(msg.sender);
  }
  /**
   * @dev add an address to the whitelist
   * @param _addr address
   */
  function addAddressToWhitelist(address _addr) onlyWhitelisted  public {
    require(_addr != address(0));
    require(!whitelist[_addr]);

    whitelist[_addr] = true;
    numberOfWhitelists++;

    emit WhitelistedAddressAdded(_addr);
  }

  /**
   * @dev remove an address from the whitelist
   * @param _addr address
   */
  function removeAddressFromWhitelist(address _addr) onlyWhitelisted  public {
    require(_addr != address(0));
    require(whitelist[_addr]);
    //the owner can not be unwhitelisted
    require(_addr != owner);

    whitelist[_addr] = false;
    numberOfWhitelists--;

    emit WhitelistedAddressRemoved(_addr);
  }

}



/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract CustomPausable is CustomWhitelist {
  event Pause();
  event Unpause();

  bool public paused = false;

  /**
   * @dev Modifier to make a function callable only when the contract is not paused.
   */
  modifier whenNotPaused() {
    require(!paused);
    _;
  }

  /**
   * @dev Modifier to make a function callable only when the contract is paused.
   */
  modifier whenPaused() {
    require(paused);
    _;
  }

  /**
   * @dev called by the owner to pause, triggers stopped state
   */
  function pause() onlyWhitelisted whenNotPaused public {
    paused = true;
    emit Pause();
  }

  /**
   * @dev called by the owner to unpause, returns to normal state
   */
  function unpause() onlyWhitelisted whenPaused public {
    paused = false;
    emit Unpause();
  }
}


/**
 * @title Vibeo: A new era of Instant Messaging/Social app allowing access to a blockchain community.
 */
contract VibeoToken is StandardToken, BurnableToken, NoOwner, CustomPausable {
  string public constant name = "Vibeo";
  string public constant symbol = "VBEO";
  uint8 public constant decimals = 18;

  uint256 public constant MAX_SUPPLY = 950000000 * (10 ** uint256(decimals)); //950 M

  ///@notice When transfers are disabled, no one except the transfer agents can use the transfer function.
  bool public transfersEnabled;

  ///@notice This signifies that the ICO was successful.
  bool public softCapReached;

  mapping(bytes32 => bool) private mintingList;

  ///@notice Transfer agents are allowed to perform transfers regardless of the transfer state.
  mapping(address => bool) private transferAgents;

  ///@notice The end date of the crowdsale. 
  uint256 public icoEndDate;
  uint256 private year = 365 * 1 days;

  event TransferAgentSet(address agent, bool state);
  event BulkTransferPerformed(address[] _destinations, uint256[] _amounts);

  constructor() public {
    mintTokens(msg.sender, 453000000);
    setTransferAgent(msg.sender, true);
  }

  ///@notice Checks if the supplied address is able to perform transfers.
  ///@param _from The address to check against if the transfer is allowed.
  modifier canTransfer(address _from) {
    if (!transfersEnabled && !transferAgents[_from]) {
      revert();
    }
    _;
  }

  ///@notice Computes keccak256 hash of the supplied value.
  ///@param _key The string value to compute hash from.
  function computeHash(string _key) private pure returns(bytes32){
    return keccak256(abi.encodePacked(_key));
  }

  ///@notice Check if the minting for the supplied key was already performed.
  ///@param _key The key or category name of minting.
  modifier whenNotMinted(string _key) {
    if(mintingList[computeHash(_key)]) {
      revert();
    }
    
    _;
  }

  ///@notice This function enables the whitelisted application (internal application) to set the ICO end date and can only be used once.
  ///@param _date The date to set as the ICO end date.
  function setICOEndDate(uint256 _date) public whenNotPaused onlyWhitelisted {
    require(icoEndDate == 0);
    icoEndDate = _date;
  }

  ///@notice This function enables the whitelisted application (internal application) to set whether or not the softcap was reached.
  //This function can only be used once.
  function setSoftCapReached() public onlyWhitelisted {
    require(!softCapReached);
    softCapReached = true;
  }

  ///@notice This function enables token transfers for everyone. Can only be enabled after the end of the ICO.
  function enableTransfers() public onlyWhitelisted {
    require(icoEndDate > 0);
    require(now >= icoEndDate);
    require(!transfersEnabled);
    transfersEnabled = true;
  }

  ///@notice This function disables token transfers for everyone.
  function disableTransfers() public onlyWhitelisted {
    require(transfersEnabled);
    transfersEnabled = false;
  }

  ///@notice Mints the tokens only once against the supplied key (category).
  ///@param _key The key or the category of the allocation to mint the tokens for.
  ///@param _amount The amount of tokens to mint.
  function mintOnce(string _key, address _to, uint256 _amount) private whenNotPaused whenNotMinted(_key) {
    mintTokens(_to, _amount);
    mintingList[computeHash(_key)] = true;
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the Vibeo team. 
  //The tokens are only available to the team after 1 year of the ICO end.
  function mintTeamTokens() public onlyWhitelisted {
    require(icoEndDate > 0);
    require(softCapReached);
    
    if(now < icoEndDate + year) {
      revert("Access is denied. The team tokens are locked for 1 year from the ICO end date.");
    }

    mintOnce("team", msg.sender, 50000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the Vibeo treasury wallet. 
  //The tokens are available only when the softcap is reached and the ICO end date is specified.
  function mintTreasuryTokens() public onlyWhitelisted {
    require(icoEndDate > 0);
    require(softCapReached);

    mintOnce("treasury", msg.sender, 90000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the Vibeo board advisors. 
  //The tokens are only available to the team after 1 year of the ICO end.
  function mintAdvisorTokens() public onlyWhitelisted {
    require(icoEndDate > 0);

    if(now < icoEndDate + year) {
      revert("Access is denied. The advisor tokens are locked for 1 year from the ICO end date.");
    }

    mintOnce("advisorsTokens", msg.sender, 80000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the Vibeo partners. 
  //The tokens are immediately available once the softcap is reached.
  function mintPartnershipTokens() public onlyWhitelisted {
    require(softCapReached);
    mintOnce("partnerships", msg.sender, 60000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to reward the Vibeo community. 
  //The tokens are immediately available once the softcap is reached.
  function mintCommunityRewards() public onlyWhitelisted {
    require(softCapReached);
    mintOnce("communityRewards", msg.sender, 90000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to Vibeo user adoption. 
  //The tokens are immediately available once the softcap is reached and ICO end date is specified.
  function mintUserAdoptionTokens() public onlyWhitelisted {
    require(icoEndDate > 0);
    require(softCapReached);

    mintOnce("useradoption", msg.sender, 95000000);
  }

  ///@notice Mints the below-mentioned amount of tokens allocated to the Vibeo marketing channel. 
  //The tokens are immediately available once the softcap is reached.
  function mintMarketingTokens() public onlyWhitelisted {
    require(softCapReached);
    mintOnce("marketing", msg.sender, 32000000);
  }

  ///@notice Enables or disables the specified address to become a transfer agent.
  //Transfer agents are such wallet addresses which can perform transfers even when transfer state is disabled.
  ///@param _agent The wallet address of the transfer agent to assign or update.
  ///@param _state Sets the status of the supplied wallet address to be a transfer agent. 
  ///When this is set to false, the address will no longer be considered as a transfer agent.
  function setTransferAgent(address _agent, bool _state) public whenNotPaused onlyWhitelisted {
    transferAgents[_agent] = _state;
    emit TransferAgentSet(_agent, _state);
  }

  ///@notice Checks if the specified address is a transfer agent.
  ///@param _address The wallet address of the transfer agent to assign or update.
  ///When this is set to false, the address will no longer be considered as a transfer agent.
  function isTransferAgent(address _address) public constant onlyWhitelisted returns(bool) {
    return transferAgents[_address];
  }

  ///@notice Transfers the specified value of tokens to the destination address. 
  //Transfers can only happen when the tranfer state is enabled. 
  //Transfer state can only be enabled after the end of the crowdsale.
  ///@param _to The destination wallet address to transfer funds to.
  ///@param _value The amount of tokens to send to the destination address.
  function transfer(address _to, uint256 _value) public whenNotPaused canTransfer(msg.sender) returns (bool) {
    require(_to != address(0));
    return super.transfer(_to, _value);
  }

  ///@notice Mints the supplied value of the tokens to the destination address.
  //Minting cannot be performed any further once the maximum supply is reached.
  //This function is private and cannot be used by anyone except for this contract.
  ///@param _to The address which will receive the minted tokens.
  ///@param _value The amount of tokens to mint.
  function mintTokens(address _to, uint256 _value) private {
    require(_to != address(0));
    _value = _value.mul(10 ** uint256(decimals));
    require(totalSupply_.add(_value) <= MAX_SUPPLY);

    totalSupply_ = totalSupply_.add(_value);
    balances[_to] = balances[_to].add(_value);
  }

  ///@notice Transfers tokens from a specified wallet address.
  ///@dev This function is overriden to leverage transfer state feature.
  ///@param _from The address to transfer funds from.
  ///@param _to The address to transfer funds to.
  ///@param _value The amount of tokens to transfer.
  function transferFrom(address _from, address _to, uint256 _value) canTransfer(_from) public returns (bool) {
    require(_to != address(0));
    return super.transferFrom(_from, _to, _value);
  }

  ///@notice Approves a wallet address to spend on behalf of the sender.
  ///@dev This function is overriden to leverage transfer state feature.
  ///@param _spender The address which is approved to spend on behalf of the sender.
  ///@param _value The amount of tokens approve to spend. 
  function approve(address _spender, uint256 _value) public canTransfer(msg.sender) returns (bool) {
    require(_spender != address(0));
    return super.approve(_spender, _value);
  }


  ///@notice Increases the approval of the spender.
  ///@dev This function is overriden to leverage transfer state feature.
  ///@param _spender The address which is approved to spend on behalf of the sender.
  ///@param _addedValue The added amount of tokens approved to spend.
  function increaseApproval(address _spender, uint256 _addedValue) public canTransfer(msg.sender) returns(bool) {
    require(_spender != address(0));
    return super.increaseApproval(_spender, _addedValue);
  }

  ///@notice Decreases the approval of the spender.
  ///@dev This function is overriden to leverage transfer state feature.
  ///@param _spender The address of the spender to decrease the allocation from.
  ///@param _subtractedValue The amount of tokens to subtract from the approved allocation.
  function decreaseApproval(address _spender, uint256 _subtractedValue) public canTransfer(msg.sender) whenNotPaused returns (bool) {
    require(_spender != address(0));
    return super.decreaseApproval(_spender, _subtractedValue);
  }

  ///@notice Returns the sum of supplied values.
  ///@param _values The collection of values to create the sum from.  
  function sumOf(uint256[] _values) private pure returns(uint256) {
    uint256 total = 0;

    for (uint256 i = 0; i < _values.length; i++) {
      total = total.add(_values[i]);
    }

    return total;
  }

  ///@notice Allows only the admins and/or whitelisted applications to perform bulk transfer operation.
  ///@param _destinations The destination wallet addresses to send funds to.
  ///@param _amounts The respective amount of fund to send to the specified addresses. 
  function bulkTransfer(address[] _destinations, uint256[] _amounts) public onlyWhitelisted {
    require(_destinations.length == _amounts.length);

    //Saving gas by determining if the sender has enough balance
    //to post this transaction.
    uint256 requiredBalance = sumOf(_amounts);
    require(balances[msg.sender] >= requiredBalance);
    
    for (uint256 i = 0; i < _destinations.length; i++) {
     transfer(_destinations[i], _amounts[i]);
    }

    emit BulkTransferPerformed(_destinations, _amounts);
  }

  ///@notice Burns the coins held by the sender.
  ///@param _value The amount of coins to burn.
  ///@dev This function is overriden to leverage Pausable feature.
  function burn(uint256 _value) public whenNotPaused {
    super.burn(_value);
  }
}