function setVaultAddress(address _vaultAddress) external override onlyOwner {
  require(vaultAddress != _vaultAddress);
  emit VaultAddress(_vaultAddress);
  vaultAddress = _vaultAddress;
}
function flash(
  address recipient,
  uint256 amount0,
  uint256 amount1,
  bytes calldata data
) external override lock {
  [...]

  address vault = IAlgebraFactory(factory).vaultAddress();

  uint256 paid0 = balanceToken0();
  require(balance0Before.add(fee0) <= paid0, 'F0');
  paid0 -= balance0Before;

  if (paid0 > 0) {
    uint8 _communityFeeToken0 = globalState.communityFeeToken0;
    uint256 fees0;
    if (_communityFeeToken0 > 0) {
      fees0 = (paid0 * _communityFeeToken0) / Constants.COMMUNITY_FEE_DENOMINATOR;
      TransferHelper.safeTransfer(token0, vault, fees0); // @audit-info `vault` is used as the recipient of community fees
    }
    totalFeeGrowth0Token += FullMath.mulDiv(paid0 - fees0, Constants.Q128, _liquidity);
  }

  uint256 paid1 = balanceToken1();
  require(balance1Before.add(fee1) <= paid1, 'F1');
  paid1 -= balance1Before;

  if (paid1 > 0) {
    uint8 _communityFeeToken1 = globalState.communityFeeToken1;
    uint256 fees1;
    if (_communityFeeToken1 > 0) {
      fees1 = (paid1 * _communityFeeToken1) / Constants.COMMUNITY_FEE_DENOMINATOR;
      TransferHelper.safeTransfer(token1, vault, fees1); // @audit-info `vault` is used as the recipient of community fees
    }
    totalFeeGrowth1Token += FullMath.mulDiv(paid1 - fees1, Constants.Q128, _liquidity);
  }

  emit Flash(msg.sender, recipient, amount0, amount1, paid0, paid1);
}
function _payCommunityFee(address token, uint256 amount) private {
  address vault = IAlgebraFactory(factory).vaultAddress();
  TransferHelper.safeTransfer(token, vault, amount);
}
