// SPDX-License-Identifier: MIT

    pragma solidity ^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);
    }


    // File @openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol@v4.3.1


    /**
    * @dev Interface for the optional metadata functions from the ERC20 standard.
    *
    * _Available since v4.1._
    */
    interface IERC20Metadata is IERC20 {
        /**
        * @dev Returns the name of the token.
        */
        function name() external view returns (string memory);

        /**
        * @dev Returns the symbol of the token.
        */
        function symbol() external view returns (string memory);

        /**
        * @dev Returns the decimals places of the token.
        */
        function decimals() external view returns (uint8);
    }


    // File @openzeppelin/contracts/utils/Context.sol@v4.3.1


    pragma solidity ^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 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) {
            return msg.sender;
        }

        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }


    // File @openzeppelin/contracts/token/ERC20/ERC20.sol@v4.3.1


    pragma solidity ^0.8.0;



    /**
    * @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 Contracts guidelines: functions revert
    * instead 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, IERC20Metadata {
        mapping(address => uint256) private _balances;

        mapping(address => mapping(address => uint256)) private _allowances;

        uint256 private _totalSupply;

        string private _name;
        string private _symbol;

        /**
        * @dev Sets the values for {name} and {symbol}.
        *
        * The default value of {decimals} is 18. To select a different value for
        * {decimals} you should overload it.
        *
        * All two of these values are immutable: they can only be set once during
        * construction.
        */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }

        /**
        * @dev Returns the name of the token.
        */
        function name() public view virtual override returns (string memory) {
            return _name;
        }

        /**
        * @dev Returns the symbol of the token, usually a shorter version of the
        * name.
        */
        function symbol() public view virtual override 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 this function is
        * overridden;
        *
        * 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 override returns (uint8) {
            return 18;
        }

        /**
        * @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);

            uint256 currentAllowance = _allowances[sender][_msgSender()];
            require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
            unchecked {
                _approve(sender, _msgSender(), currentAllowance - amount);
            }

            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] + 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) {
            uint256 currentAllowance = _allowances[_msgSender()][spender];
            require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
            unchecked {
                _approve(_msgSender(), spender, currentAllowance - subtractedValue);
            }

            return true;
        }

        /**
        * @dev Moves `amount` of tokens from `sender` to `recipient`.
        *
        * This 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);

            uint256 senderBalance = _balances[sender];
            require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
            unchecked {
                _balances[sender] = senderBalance - amount;
            }
            _balances[recipient] += amount;

            emit Transfer(sender, recipient, amount);

            _afterTokenTransfer(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:
        *
        * - `account` 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 += amount;
            _balances[account] += amount;
            emit Transfer(address(0), account, amount);

            _afterTokenTransfer(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);

            uint256 accountBalance = _balances[account];
            require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
            unchecked {
                _balances[account] = accountBalance - amount;
            }
            _totalSupply -= amount;

            emit Transfer(account, address(0), amount);

            _afterTokenTransfer(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 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 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 {}

        /**
        * @dev Hook that is called after any transfer of tokens. This includes
        * minting and burning.
        *
        * Calling conditions:
        *
        * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
        * has been transferred to `to`.
        * - when `from` is zero, `amount` tokens have been minted for `to`.
        * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual {}
    }


    // File @openzeppelin/contracts/access/Ownable.sol@v4.3.1


    /**
    * @dev Contract module which provides a basic access control mechanism, where
    * there is an account (an owner) that can be granted exclusive access to
    * specific functions.
    *
    * By default, the owner account will be the one that deploys the contract. This
    * can later be changed with {transferOwnership}.
    *
    * This module is used through inheritance. It will make available the modifier
    * `onlyOwner`, which can be applied to your functions to restrict their use to
    * the owner.
    */
    abstract contract Ownable is Context {
        address private _owner;

        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

        /**
        * @dev Initializes the contract setting the deployer as the initial owner.
        */
        constructor() {
            _setOwner(_msgSender());
        }

        /**
        * @dev Returns the address of the current owner.
        */
        function owner() public view virtual returns (address) {
            return _owner;
        }

        /**
        * @dev Throws if called by any account other than the owner.
        */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }


        /**
        * @dev Transfers ownership of the contract to a new account (`newOwner`).
        * Can only be called by the current owner.
        */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _setOwner(newOwner);
        }

        function _setOwner(address newOwner) private {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }

    contract TZIVA is ERC20, Ownable {
    constructor() ERC20("TradeZiva", "TZIVA") {
    _mint(msg.sender, 100000000000 * 10 ** decimals());
    }
    }