└── Auction.sol


/Auction.sol:
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 1 | // SPDX-License-Identifier: MIT
 2 | pragma solidity ^0.8.0;
 3 | 
 4 | contract Auction {
 5 |     address public owner;
 6 |     uint256 public highestBid;
 7 |     address public highestBidder;
 8 | 
 9 |     constructor() {
10 |         owner = msg.sender;
11 |         highestBid = 0;
12 |     }
13 | 
14 |     function bid() public payable {
15 |         require(msg.value > highestBid, "Bid must be higher than current highest bid");
16 |         if (highestBid != 0) {
17 |             payable(highestBidder).transfer(highestBid); // Refund the previous highest bidder
18 |         }
19 |         highestBid = msg.value;
20 |         highestBidder = msg.sender;
21 |     }
22 | 
23 |     function finalize() public {
24 |         require(msg.sender == owner, "Only owner can finalize the auction");
25 |         payable(owner).transfer(highestBid);
26 |         highestBid = 0;
27 |     }
28 | }
29 | 


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