30 lines
732 B
Solidity
30 lines
732 B
Solidity
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/*
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* @source: https://capturetheether.com/challenges/lotteries/guess-the-random-number/
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* @author: Steve Marx
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* @vulnerable_at_lines: 15
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*/
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pragma solidity ^0.4.21;
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contract GuessTheRandomNumberChallenge {
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uint8 answer;
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function GuessTheRandomNumberChallenge() public payable {
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require(msg.value == 1 ether);
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// <yes> <report> BAD_RANDOMNESS
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answer = uint8(keccak256(block.blockhash(block.number - 1), now));
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}
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function isComplete() public view returns (bool) {
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return address(this).balance == 0;
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}
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function guess(uint8 n) public payable {
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require(msg.value == 1 ether);
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if (n == answer) {
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msg.sender.transfer(2 ether);
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}
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}
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}
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