04.Guess the new number
2023-06-23 20:22:15 # 01.Capturetheether CTF

Guess the new number

topic

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pragma solidity ^0.4.21;

contract GuessTheNewNumberChallenge {
function GuessTheNewNumberChallenge() public payable {
require(msg.value == 1 ether);
}

function isComplete() public view returns (bool) {
return address(this).balance == 0;
}

function guess(uint8 n) public payable {
require(msg.value == 1 ether);
uint8 answer = uint8(keccak256(block.blockhash(block.number - 1), now));

if (n == answer) {
msg.sender.transfer(2 ether);
}
}
}

analyses

the same as the article in my blog: [security-12]

solution

the same as the article in my blog: [security-12]