{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"How does blockchain prevent the double-spending problem?","a":"Blockchain prevents double-spending issues by introducing techniques such as timestamps, UTXO model, and consensus mechanisms. Firstly, in cryptocurrency systems like Bitcoin,  each transaction has a unique timestamp to ensure the correctness of the transaction order. Secondly, the UTXO (Unspent Transaction Output) model is used to record the balance of each cryptocurrency address, and only UTXOs that have been confirmed in previous transactions can be used in new transactions. Lastly, consensus mechanisms (such as proof of work) ensure the security of transactions in blockchain networks, making double-spending attacks very difficult.↵↵Specifically, when a transaction is broadcasted to the blockchain network,"}]}],"pr":"6fe332f91c6013e6d3c2357e2d4727492a25b6aa61391972da8659314c1fb9ab"}