contract KemfeCoin is ERC20Interface {
   
    using SafeMath for uint256;
    string public constant symbol = "KFC";
    string public constant name = "KFC";
    uint8 public constant decimals = 18;
    uint256 _totalSupply = 500000000000000000000000000;
 
     struct LockAccount{
        uint status;
    }

     mapping (address => LockAccount) lockAccount;
     address[] public AllLockAccounts;
    
    
    // Owner of this contract
    address public owner;

    // Balances for each account
    mapping (address => uint256) balances;

    // Owner of account approves the transfer of an amount to another account
    mapping (address => mapping (address => uint256)) allowed;

    // Functions with this modifier can only be executed by the owner
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    //Constructor
    constructor() public {
        owner = msg.sender;
        balances[owner] = _totalSupply;
    }
    

    function totalSupply() view public returns (uint256) {
        return _totalSupply;
    }
    
    
       function setLockAccount(address _addr) public{
        require(msg.sender == owner);
       
        lockAccount[_addr].status = 1;
        AllLockAccounts.push(_addr) -1;
    }
    
      function getLockAccounts() view public returns (address[] memory){
        return AllLockAccounts;
    }
      function unLockAccount(address _addr) public {
        require(msg.sender == owner);
       lockAccount[_addr].status = 0;
       
    }
    
    function isLock (address _addr) view private returns(bool){
        uint lS = lockAccount[_addr].status;
        
        if(lS == 1){
            return true;
        }
        
        return false;
    }

   
     function getLockAccount(address _addr) view public returns (uint){
        return lockAccount[_addr].status;
    }

    // What is the balance of a particular account?
    function balanceOf(address _owner) view public returns (uint256) {
        return balances[_owner];
    }

    // Transfer the balance from owner's account to another account
    function transfer(address _to, uint256 _amount) public returns (bool success) {
        if (balances[msg.sender] >= _amount
        && _amount > 0
        && balances[_to] + _amount > balances[_to]) {
            balances[msg.sender] = balances[msg.sender].sub(_amount);
            balances[_to] = balances[_to].add(_amount);
            emit Transfer(msg.sender, _to, _amount);
            return true;
        }
        else {
            return false;
        }
    }

    // Send _value amount of tokens from address _from to address _to
    // The transferFrom method is used for a withdraw workflow, allowing contracts to send
    // tokens on your behalf, for example to "deposit" to a contract address and/or to charge
    // fees in sub-currencies; the command should fail unless the _from account has
    // deliberately authorized the sender of the message via some mechanism; we propose
    // these standardized APIs for approval:
    function transferFrom(
    address _from,
    address _to,
    uint256 _amount
    ) public returns (bool) {
        if (balances[_from] >= _amount
        && allowed[_from][msg.sender] >= _amount
        && _amount > 0
        && balances[_to] + _amount > balances[_to]) {
            balances[_from] = balances[_from].sub(_amount);
            allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_amount);
            balances[_to] = balances[_to].add(_amount);
            emit Transfer(_from, _to, _amount);
            return true;
        }
        else {
            return false;
        }
    }


    // Allow _spender to withdraw from your account, multiple times, up to the _value amount.
    // If this function is called again it overwrites the current allowance with _value.
    function approve(address _spender, uint256 _amount) public returns (bool success) {
        allowed[msg.sender][_spender] = _amount;
        emit Approval(msg.sender, _spender, _amount);
        return true;
    }

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

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

// Allow _spender to withdraw from your account, multiple times, up to the _value amount.
// If this function is called again it overwrites the current allowance with _value.