remove observed contract

contracts/dividend.sol

@@ -243,7 +243,7 @@ contract DividendContract is Initializable, UUPSUpgradeable, ReentrancyGuardUpgr
 
  // stake tokens to next cycle
  function stake(uint256 amount) external nonReentrant {
- require(amount > 0, "Cannot stake 0");
+ require(amount >0, "Cannot stake 0 DMC");
  require(IERC20(stakingToken).transferFrom(msg.sender, address(this), amount), "Stake failed");
 
  console.log("user stake ===> amount %d, cycle %d, user %s", amount, currentCycleIndex, msg.sender);
@@ -262,6 +262,7 @@ contract DividendContract is Initializable, UUPSUpgradeable, ReentrancyGuardUpgr
 
  // update the total staked amount of the contract
  totalStaked += amount;
+ //TODO: update current cycle's total staked?
 
  // emit the stake event
  emit Stake(msg.sender, amount);

contracts/dmc2.sol

@@ -6,6 +6,7 @@ import "@openzeppelin/contracts/access/Ownable.sol";
 
 contract DMC2 is ERC20Burnable, Ownable {
  mapping (address => bool) allow_minter;
+ bool can_change_minter = true;
 
  modifier onlyMinter() {
  require(allow_minter[msg.sender], "mint not allowed");
@@ -20,14 +21,20 @@ contract DMC2 is ERC20Burnable, Ownable {
  }
  _mint(address(this), _totalSupply - totalInited);
  }
+
+ function disableMinterChange() public onlyOwner {
+ can_change_minter = false;
+ }
 
  function enableMinter(address[] calldata addresses) public onlyOwner {
+ require(can_change_minter, "mint change not allowed");
  for (uint i = 0; i < addresses.length; i++) {
  allow_minter[addresses[i]] = true;
  }
  }
 
  function disableMinter(address[] calldata addresses) public onlyOwner {
+ require(can_change_minter, "mint change not allowed");
  for (uint i = 0; i < addresses.length; i++) {
  allow_minter[addresses[i]] = false;
  }