WhiteList.sol

//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.0;

contract Whitelist {
   
    uint8 public maxAddresses;

    mapping(address => bool) public whitelistedAddresses;

    uint8 public numAddressesWhitelisted;

    constructor(uint8 _maxWhitelistedAddresses) {
        maxAddresses =  _maxWhitelistedAddresses;
    }


    function addAddressToWhitelist() public {
       
        require(!whitelistedAddresses[msg.sender], "Sender has already been whitelisted");
     
        require(numAddressesWhitelisted < maxAddresses, "More addresses cant be added, limit reached");
       
        whitelistedAddresses[msg.sender] = true;
      
        numAddressesWhitelisted += 1;
    }
}