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@woodydeck
Forked from alexvandesande/Random generator
Created April 14, 2018 06:20
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A very simple random generator. A miner can influence the number by not publishing a block with an unwanted outcome, and forfeiting the 5 block reward.
contract random {
/* Generates a random number from 0 to 100 based on the last block hash */
function randomGen(uint seed) constant returns (uint randomNumber) {
return(uint(sha3(block.blockhash(block.number-1), seed ))%100);
}
/* generates a number from 0 to 2^n based on the last n blocks */
function multiBlockRandomGen(uint seed, uint size) constant returns (uint randomNumber) {
uint n = 0;
for (uint i = 0; i < size; i++){
if (uint(sha3(block.blockhash(block.number-i-1), seed ))%2==0)
n += 2**i;
}
return n;
}
}
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