Hi, I have a question for you pls. Does it means that a miner could hack the bitcoins from who really worked out the puzzles? Because once he signed the transaction, the miners knows the public key and if they know this is for the puzzles, they can utilize your method to find corresponding private key and hacked the funds.
For what all guys are saying here - seems like each and every random transaction should be possible to be stolen just knowing the public key. At any time when it is still in mempool. Not only puzzle addresses.
No, it isn't! Read carefully the details to understand. If you have further questions don't hesitate to put them. This is true only for low-bit ranges. Let's say I make an outgoing transaction from my own bitcoin address which I generated using a 256bit key. You will know the pubkey but you won't be able to bruteforce because you'll never survive it

But if I used a 66bit key then you can crack the privkey in less than 10 seconds.