Example contract for TOD mitigation.

TODFix.sol

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

contract numGuess {
    address public winner; 
    mapping (address => bytes32) public playerHashes; 

    function storeHash(bytes32 _hash) external {
        playerHashes[msg.sender] = _hash; 
    }

    function guess(uint _answer, uint _salt) external {
        require (keccak256(abi.encodePacked(_answer, _salt, msg.sender)) == playerHashes[msg.sender]);
        require (_answer == 9841984198);
        winner = msg.sender;
    }
}