// Dependency file: @openzeppelin/contracts/token/ERC20/IERC20.sol

// SPDX-License-Identifier: MIT

// pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
	/**
	 * @dev Returns the amount of tokens in existence.
	 */
	function totalSupply() external view returns (uint256);

	/**
	 * @dev Returns the amount of tokens owned by `account`.
	 */
	function balanceOf(address account) external view returns (uint256);

	/**
	 * @dev Moves `amount` tokens from the caller's account to `recipient`.
	 *
	 * Returns a boolean value indicating whether the operation succeeded.
	 *
	 * Emits a {Transfer} event.
	 */
	function transfer(address recipient, uint256 amount) external returns (bool);

	/**
	 * @dev Returns the remaining number of tokens that `spender` will be
	 * allowed to spend on behalf of `owner` through {transferFrom}. This is
	 * zero by default.
	 *
	 * This value changes when {approve} or {transferFrom} are called.
	 */
	function allowance(address owner, address spender) external view returns (uint256);

	/**
	 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
	 *
	 * Returns a boolean value indicating whether the operation succeeded.
	 *
	 * IMPORTANT: 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
	 *
	 * Emits an {Approval} event.
	 */
	function approve(address spender, uint256 amount) external returns (bool);

	/**
	 * @dev Moves `amount` tokens from `sender` to `recipient` using the
	 * allowance mechanism. `amount` is then deducted from the caller's
	 * allowance.
	 *
	 * Returns a boolean value indicating whether the operation succeeded.
	 *
	 * Emits a {Transfer} event.
	 */
	function transferFrom(
		address sender,
		address recipient,
		uint256 amount
	) external returns (bool);

	/**
	 * @dev Emitted when `value` tokens are moved from one account (`from`) to
	 * another (`to`).
	 *
	 * Note that `value` may be zero.
	 */
	event Transfer(address indexed from, address indexed to, uint256 value);

	/**
	 * @dev Emitted when the allowance of a `spender` for an `owner` is set by
	 * a call to {approve}. `value` is the new allowance.
	 */
	event Approval(address indexed owner, address indexed spender, uint256 value);
}

// Dependency file: @openzeppelin/contracts/utils/Context.sol

// pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
	function _msgSender() internal view virtual returns (address payable) {
		return msg.sender;
	}

	function _msgData() internal view virtual returns (bytes memory) {
		this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
		return msg.data;
	}
}

// Dependency file: @openzeppelin/contracts/math/SafeMath.sol

// pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
	/**
	 * @dev Returns the addition of two unsigned integers, with an overflow flag.
	 *
	 * _Available since v3.4._
	 */
	function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
		uint256 c = a + b;
		if (c < a) return (false, 0);
		return (true, c);
	}

	/**
	 * @dev Returns the substraction of two unsigned integers, with an overflow flag.
	 *
	 * _Available since v3.4._
	 */
	function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
		if (b > a) return (false, 0);
		return (true, a - b);
	}

	/**
	 * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
	 *
	 * _Available since v3.4._
	 */
	function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
		// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
		// benefit is lost if 'b' is also tested.
		// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
		if (a == 0) return (true, 0);
		uint256 c = a * b;
		if (c / a != b) return (false, 0);
		return (true, c);
	}

	/**
	 * @dev Returns the division of two unsigned integers, with a division by zero flag.
	 *
	 * _Available since v3.4._
	 */
	function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
		if (b == 0) return (false, 0);
		return (true, a / b);
	}

	/**
	 * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
	 *
	 * _Available since v3.4._
	 */
	function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
		if (b == 0) return (false, 0);
		return (true, a % b);
	}

	/**
	 * @dev Returns the addition of two unsigned integers, reverting on
	 * overflow.
	 *
	 * Counterpart to Solidity's `+` operator.
	 *
	 * Requirements:
	 *
	 * - Addition cannot overflow.
	 */
	function add(uint256 a, uint256 b) internal pure returns (uint256) {
		uint256 c = a + b;
		require(c >= a, 'SafeMath: addition overflow');
		return c;
	}

	/**
	 * @dev Returns the subtraction of two unsigned integers, reverting on
	 * overflow (when the result is negative).
	 *
	 * Counterpart to Solidity's `-` operator.
	 *
	 * Requirements:
	 *
	 * - Subtraction cannot overflow.
	 */
	function sub(uint256 a, uint256 b) internal pure returns (uint256) {
		require(b <= a, 'SafeMath: subtraction overflow');
		return a - b;
	}

	/**
	 * @dev Returns the multiplication of two unsigned integers, reverting on
	 * overflow.
	 *
	 * Counterpart to Solidity's `*` operator.
	 *
	 * Requirements:
	 *
	 * - Multiplication cannot overflow.
	 */
	function mul(uint256 a, uint256 b) internal pure returns (uint256) {
		if (a == 0) return 0;
		uint256 c = a * b;
		require(c / a == b, 'SafeMath: multiplication overflow');
		return c;
	}

	/**
	 * @dev Returns the integer division of two unsigned integers, reverting on
	 * division by zero. The result is rounded towards zero.
	 *
	 * Counterpart to Solidity's `/` operator. Note: this function uses a
	 * `revert` opcode (which leaves remaining gas untouched) while Solidity
	 * uses an invalid opcode to revert (consuming all remaining gas).
	 *
	 * Requirements:
	 *
	 * - The divisor cannot be zero.
	 */
	function div(uint256 a, uint256 b) internal pure returns (uint256) {
		require(b > 0, 'SafeMath: division by zero');
		return a / b;
	}

	/**
	 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
	 * reverting when dividing by zero.
	 *
	 * Counterpart to Solidity's `%` operator. This function uses a `revert`
	 * opcode (which leaves remaining gas untouched) while Solidity uses an
	 * invalid opcode to revert (consuming all remaining gas).
	 *
	 * Requirements:
	 *
	 * - The divisor cannot be zero.
	 */
	function mod(uint256 a, uint256 b) internal pure returns (uint256) {
		require(b > 0, 'SafeMath: modulo by zero');
		return a % b;
	}

	/**
	 * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
	 * overflow (when the result is negative).
	 *
	 * CAUTION: This function is deprecated because it requires allocating memory for the error
	 * message unnecessarily. For custom revert reasons use {trySub}.
	 *
	 * Counterpart to Solidity's `-` operator.
	 *
	 * Requirements:
	 *
	 * - Subtraction cannot overflow.
	 */
	function sub(
		uint256 a,
		uint256 b,
		string memory errorMessage
	) internal pure returns (uint256) {
		require(b <= a, errorMessage);
		return a - b;
	}

	/**
	 * @dev Returns the integer division of two unsigned integers, reverting with custom message on
	 * division by zero. The result is rounded towards zero.
	 *
	 * CAUTION: This function is deprecated because it requires allocating memory for the error
	 * message unnecessarily. For custom revert reasons use {tryDiv}.
	 *
	 * Counterpart to Solidity's `/` operator. Note: this function uses a
	 * `revert` opcode (which leaves remaining gas untouched) while Solidity
	 * uses an invalid opcode to revert (consuming all remaining gas).
	 *
	 * Requirements:
	 *
	 * - The divisor cannot be zero.
	 */
	function div(
		uint256 a,
		uint256 b,
		string memory errorMessage
	) internal pure returns (uint256) {
		require(b > 0, errorMessage);
		return a / b;
	}

	/**
	 * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
	 * reverting with custom message when dividing by zero.
	 *
	 * CAUTION: This function is deprecated because it requires allocating memory for the error
	 * message unnecessarily. For custom revert reasons use {tryMod}.
	 *
	 * Counterpart to Solidity's `%` operator. This function uses a `revert`
	 * opcode (which leaves remaining gas untouched) while Solidity uses an
	 * invalid opcode to revert (consuming all remaining gas).
	 *
	 * Requirements:
	 *
	 * - The divisor cannot be zero.
	 */
	function mod(
		uint256 a,
		uint256 b,
		string memory errorMessage
	) internal pure returns (uint256) {
		require(b > 0, errorMessage);
		return a % b;
	}
}

// Dependency file: @openzeppelin/contracts/token/ERC20/ERC20.sol

// pragma solidity >=0.6.0 <0.8.0;

// import "@openzeppelin/contracts/utils/Context.sol";
// import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
// import "@openzeppelin/contracts/math/SafeMath.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
	using SafeMath for uint256;

	mapping(address => uint256) private _balances;

	mapping(address => mapping(address => uint256)) private _allowances;

	uint256 private _totalSupply;

	string private _name;
	string private _symbol;
	uint8 private _decimals;

	/**
	 * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
	 * a default value of 18.
	 *
	 * To select a different value for {decimals}, use {_setupDecimals}.
	 *
	 * All three of these values are immutable: they can only be set once during
	 * construction.
	 */
	constructor(string memory name_, string memory symbol_) public {
		_name = name_;
		_symbol = symbol_;
		_decimals = 18;
	}

	/**
	 * @dev Returns the name of the token.
	 */
	function name() public view virtual returns (string memory) {
		return _name;
	}

	/**
	 * @dev Returns the symbol of the token, usually a shorter version of the
	 * name.
	 */
	function symbol() public view virtual returns (string memory) {
		return _symbol;
	}

	/**
	 * @dev Returns the number of decimals used to get its user representation.
	 * For example, if `decimals` equals `2`, a balance of `505` tokens should
	 * be displayed to a user as `5,05` (`505 / 10 ** 2`).
	 *
	 * Tokens usually opt for a value of 18, imitating the relationship between
	 * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
	 * called.
	 *
	 * NOTE: This information is only used for _display_ purposes: it in
	 * no way affects any of the arithmetic of the contract, including
	 * {IERC20-balanceOf} and {IERC20-transfer}.
	 */
	function decimals() public view virtual returns (uint8) {
		return _decimals;
	}

	/**
	 * @dev See {IERC20-totalSupply}.
	 */
	function totalSupply() public view virtual override returns (uint256) {
		return _totalSupply;
	}

	/**
	 * @dev See {IERC20-balanceOf}.
	 */
	function balanceOf(address account) public view virtual override returns (uint256) {
		return _balances[account];
	}

	/**
	 * @dev See {IERC20-transfer}.
	 *
	 * Requirements:
	 *
	 * - `recipient` cannot be the zero address.
	 * - the caller must have a balance of at least `amount`.
	 */
	function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
		_transfer(_msgSender(), recipient, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-allowance}.
	 */
	function allowance(address owner, address spender) public view virtual override returns (uint256) {
		return _allowances[owner][spender];
	}

	/**
	 * @dev See {IERC20-approve}.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function approve(address spender, uint256 amount) public virtual override returns (bool) {
		_approve(_msgSender(), spender, amount);
		return true;
	}

	/**
	 * @dev See {IERC20-transferFrom}.
	 *
	 * Emits an {Approval} event indicating the updated allowance. This is not
	 * required by the EIP. See the note at the beginning of {ERC20}.
	 *
	 * Requirements:
	 *
	 * - `sender` and `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 * - the caller must have allowance for ``sender``'s tokens of at least
	 * `amount`.
	 */
	function transferFrom(
		address sender,
		address recipient,
		uint256 amount
	) public virtual override returns (bool) {
		_transfer(sender, recipient, amount);
		_approve(
			sender,
			_msgSender(),
			_allowances[sender][_msgSender()].sub(amount, 'ERC20: transfer amount exceeds allowance')
		);
		return true;
	}

	/**
	 * @dev Atomically increases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 */
	function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
		_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
		return true;
	}

	/**
	 * @dev Atomically decreases the allowance granted to `spender` by the caller.
	 *
	 * This is an alternative to {approve} that can be used as a mitigation for
	 * problems described in {IERC20-approve}.
	 *
	 * Emits an {Approval} event indicating the updated allowance.
	 *
	 * Requirements:
	 *
	 * - `spender` cannot be the zero address.
	 * - `spender` must have allowance for the caller of at least
	 * `subtractedValue`.
	 */
	function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
		_approve(
			_msgSender(),
			spender,
			_allowances[_msgSender()][spender].sub(subtractedValue, 'ERC20: decreased allowance below zero')
		);
		return true;
	}

	/**
	 * @dev Moves tokens `amount` from `sender` to `recipient`.
	 *
	 * This is internal function is equivalent to {transfer}, and can be used to
	 * e.g. implement automatic token fees, slashing mechanisms, etc.
	 *
	 * Emits a {Transfer} event.
	 *
	 * Requirements:
	 *
	 * - `sender` cannot be the zero address.
	 * - `recipient` cannot be the zero address.
	 * - `sender` must have a balance of at least `amount`.
	 */
	function _transfer(
		address sender,
		address recipient,
		uint256 amount
	) internal virtual {
		require(sender != address(0), 'ERC20: transfer from the zero address');
		require(recipient != address(0), 'ERC20: transfer to the zero address');

		_beforeTokenTransfer(sender, recipient, amount);

		_balances[sender] = _balances[sender].sub(amount, 'ERC20: transfer amount exceeds balance');
		_balances[recipient] = _balances[recipient].add(amount);
		emit Transfer(sender, recipient, amount);
	}

	/** @dev Creates `amount` tokens and assigns them to `account`, increasing
	 * the total supply.
	 *
	 * Emits a {Transfer} event with `from` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `to` cannot be the zero address.
	 */
	function _mint(address account, uint256 amount) internal virtual {
		require(account != address(0), 'ERC20: mint to the zero address');

		_beforeTokenTransfer(address(0), account, amount);

		_totalSupply = _totalSupply.add(amount);
		_balances[account] = _balances[account].add(amount);
		emit Transfer(address(0), account, amount);
	}

	/**
	 * @dev Destroys `amount` tokens from `account`, reducing the
	 * total supply.
	 *
	 * Emits a {Transfer} event with `to` set to the zero address.
	 *
	 * Requirements:
	 *
	 * - `account` cannot be the zero address.
	 * - `account` must have at least `amount` tokens.
	 */
	function _burn(address account, uint256 amount) internal virtual {
		require(account != address(0), 'ERC20: burn from the zero address');

		_beforeTokenTransfer(account, address(0), amount);

		_balances[account] = _balances[account].sub(amount, 'ERC20: burn amount exceeds balance');
		_totalSupply = _totalSupply.sub(amount);
		emit Transfer(account, address(0), amount);
	}

	/**
	 * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
	 *
	 * This internal function is equivalent to `approve`, and can be used to
	 * e.g. set automatic allowances for certain subsystems, etc.
	 *
	 * Emits an {Approval} event.
	 *
	 * Requirements:
	 *
	 * - `owner` cannot be the zero address.
	 * - `spender` cannot be the zero address.
	 */
	function _approve(
		address owner,
		address spender,
		uint256 amount
	) internal virtual {
		require(owner != address(0), 'ERC20: approve from the zero address');
		require(spender != address(0), 'ERC20: approve to the zero address');

		_allowances[owner][spender] = amount;
		emit Approval(owner, spender, amount);
	}

	/**
	 * @dev Sets {decimals} to a value other than the default one of 18.
	 *
	 * WARNING: This function should only be called from the constructor. Most
	 * applications that interact with token contracts will not expect
	 * {decimals} to ever change, and may work incorrectly if it does.
	 */
	function _setupDecimals(uint8 decimals_) internal virtual {
		_decimals = decimals_;
	}

	/**
	 * @dev Hook that is called before any transfer of tokens. This includes
	 * minting and burning.
	 *
	 * Calling conditions:
	 *
	 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
	 * will be to transferred to `to`.
	 * - when `from` is zero, `amount` tokens will be minted for `to`.
	 * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
	 * - `from` and `to` are never both zero.
	 *
	 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
	 */
	function _beforeTokenTransfer(
		address from,
		address to,
		uint256 amount
	) internal virtual {}
}

// Dependency file: contracts/libraries/Upgradable.sol

// pragma solidity >=0.6.5 <0.8.0;

contract UpgradableProduct {
	address public impl;

	event ImplChanged(address indexed _oldImpl, address indexed _newImpl);

	constructor() public {
		impl = msg.sender;
	}

	modifier requireImpl() {
		require(msg.sender == impl, 'FORBIDDEN');
		_;
	}

	function upgradeImpl(address _newImpl) public requireImpl {
		require(_newImpl != address(0), 'INVALID_ADDRESS');
		require(_newImpl != impl, 'NO_CHANGE');
		address lastImpl = impl;
		impl = _newImpl;
		emit ImplChanged(lastImpl, _newImpl);
	}
}

contract UpgradableGovernance {
	address public governor;

	event GovernorChanged(address indexed _oldGovernor, address indexed _newGovernor);

	constructor() public {
		governor = msg.sender;
	}

	modifier requireGovernor() {
		require(msg.sender == governor, 'FORBIDDEN');
		_;
	}

	function upgradeGovernance(address _newGovernor) public requireGovernor {
		require(_newGovernor != address(0), 'INVALID_ADDRESS');
		require(_newGovernor != governor, 'NO_CHANGE');
		address lastGovernor = governor;
		governor = _newGovernor;
		emit GovernorChanged(lastGovernor, _newGovernor);
	}
}

// Root file: contracts/CheeseToken.sol

// pragma solidity >=0.6.5 <0.8.0;

contract CheeseToken is ERC20, UpgradableProduct {
	using SafeMath for uint256;

	mapping(address => bool) public whiteList;

	constructor(string memory _symbol, string memory _name) public ERC20(_name, _symbol) {
		_mint(msg.sender, uint256(2328300).mul(1e18));
	}

	modifier onlyWhitelisted() {
		require(whiteList[msg.sender], '!whitelisted');
		_;
	}

	function setWhitelist(address _toWhitelist, bool _state) external requireImpl {
		whiteList[_toWhitelist] = _state;
	}

	function mint(address account, uint256 amount) external virtual onlyWhitelisted {
		require(totalSupply().add(amount) <= cap(), 'ERC20Capped: cap exceeded');
		_mint(account, amount);
	}

	function cap() public pure virtual returns (uint256) {
		return 9313200 * 1e18;
	}

	function burnFrom(address account, uint256 amount) public virtual {
		uint256 decreasedAllowance = allowance(account, _msgSender()).sub(
			amount,
			'ERC20: burn amount exceeds allowance'
		);
		_approve(account, _msgSender(), decreasedAllowance);
		_burn(account, amount);
	}

	function burn(uint256 amount) external virtual {
		_burn(_msgSender(), amount);
	}
}