constructor (address _token ) public {
    symbol = 0;
    token = _token;
}

function burn( address _sender, uint256 value ) public onlyOwner( _sender ) {
    require(ERC20(token).transferFrom( _sender, address(this), value), 'transferFrom erro');
    burnList[_sender].amount = burnList[_sender].amount.add(value);
    symbol = symbol.add(value);
    emit Burn( _sender, value);
}

function fetchMeer( bytes20 _meerPKH ) public {
    burnList[msg.sender].redeemPublicHash = _meerPKH;
}

function getSenderNum( address _sender ) view public returns(uint) {
    return burnList[_sender].redeem.length;
}

function getSender( address _sender, uint i ) view public returns( bytes20 meerPublickeyHash, bytes32 txId, uint256 amount ) {
    BurnList memory burn = burnList[_sender];
    return ( burn.redeem[i].meerPKH, burn.redeem[i].txId, burn.redeem[i].amount );
}

function confirmTxid( address _sender, bytes32 txId, uint256 meerNum ) public only(owner) {
    BurnList memory burner = burnList[_sender];
    require( burner.amount > 0 );
    require( burner.redeemPublicHash != 0x0 );
    burnList[_sender].redeem.push(
        Redeem(
            burner.redeemPublicHash,
            txId,
            meerNum
        )
    );
    burnList[_sender].amount = 0;
}