Bitcoin scripting puzzle from the MIT Expo

jonald_fyookball

legendary

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Core dev leaves me neg feedback #abuse #political

you have to be a real expert in Bitcoin to even understand this. non Bitcoin nerds need not apply.

halftimepad

newbie

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Quote from: telepatheic on May 04, 2014, 04:43:37 AM

The main-net puzzle has been solved https://blockchain.info/tx/f00f5da308a948aa019de92428c7fa1c89587414f56beee7074135d46dad793d

And there is a new puzzle

http://blockexplorer.com/testnet/tx/44b9f9ff28fbfc33d4824729b2ec6f2929588faef81717e194fd7fe2a6b5d384

I don't think you can spend the second output of the transaction. The script is:

OP_HASH256 OP_HASH256 0 ffffffffffffffffffffffffffffffffffffffffffff OP_WITHIN

It seems the sender wanted a problem similar to mining: find a string with a low hash and get the reward.

But OP_WITHIN and all the arithmetic operators only work for inputs of up to 4 bytes. Quoting from
https://en.bitcoin.it/wiki/Script#Arithmetic
"If any input value for any of these commands is longer than 4 bytes, the script must abort and fail."

ffffffffffffffffffffffffffffffffffffffffffff has 22 bytes. OP_WITHIN will cause the script to fail, no matter what inputs you choose. These bitcoins are irredeemable.

telepatheic

jr. member

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