Dieser Vertrag implementiert nicht alle Funktionen und kann daher nicht veröffentlicht werden

Bei Remix erhalte ich beim Implementieren des hier vorgeschlagenen Vertrags - https://www.youtube.com/watch?v=JHrQ3l2tT78 - die Fehlermeldung "Dieser Vertrag implementiert nicht alle Funktionen und kann daher nicht veröffentlicht werden."

Ich habe andere Beiträge gesehen, die besagen, dass die Konstruktorfunktion Parameter auflisten muss, aber ich habe erfolglos versucht, Parameter zu „NewToken“ hinzuzufügen. Vielleicht füge ich diese falsch hinzu, aber da das tut keine hat, denke ich, dass ich vielleicht etwas anderes falsch mache.

Schätzen Sie jede Hilfe.

pragma solidity ^0.4.11;

import './IERC20.sol';

/**
 * @title Standard ERC20 token
 */
contract NewToken is IERC20 {

    uint public constant _totalSupply = 1000000;
    uint8 public constant _decimals = 3;
    string public constant _symbol = 'NTK';
    string public constant _name = 'NewToken';

    mapping(address => uint256) balances;
    mapping(address => mapping(address => uint256)) approved;


    function NewToken() public {
        balances[msg.sender] = _totalSupply;
    }

    function decimals() public constant returns (uint8 decimals) {
        return _decimals;
    }

    function totalSupply() public constant returns (uint256 totalSupply) {
        return _totalSupply;
    }

    function balanceOf(address _owner) public constant returns (uint256 balance) {
        return balances[_owner];
    }

    function transfer(address _to, uint256 _value) public returns (bool success) {
        require(
            balances[msg.sender] >= _value && _value > 0    
        );
        balances[msg.sender] -= _value;
        balances[_to] += _value;
        Transfer(msg.sender, _to, _value);
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(
            approved[_from][msg.sender] >= _value && balances[_from] >= _value && _value > 0
        );
        balances[_from] -= _value;
        balances[_to] += _value;
        approved[_from][msg.sender] -= _value;
        Transfer(_from, _to, _value);
        return true;
    }

    function approve(address _spender, uint256 _value) public returns (bool success) {
        approved[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
        return approved[_owner][_spender];
    }

    event Transfer(address indexed _from, address indexed _to, uint256 _value);

    event Approval(address indexed _owner, address indexed _spender, uint256 _value);

}

IERC20.sol

pragma solidity ^0.4.11;

interface IERC20 {
    function decimals() public constant returns (uint8 decimals);
    function totalSupply() public constant returns (uint256 totalSupply);
    function balanceOf(address _owner) public constant returns (uint256 balance);
    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);
}