{"p":"can-20","op":"mint","tick":"can","amt":"1000","rows":[{"df":"qa","content":[{"q":"How is the double-spending problem solved in blockchain?","a":"The double-spending problem in blockchain is solved by various technologies and consensus mechanisms. Firstly, decentralized peer-to-peer value transfer systems such as Bitcoin utilize the UTXO (Unspent Transaction Output) model to prevent the same digital asset from being double-used. When a transaction is broadcasted to the blockchain network, the  nodes that receive the transaction will validate whether the transaction contains already-spent UTXOs. If the transaction output does not exist in the unspent transaction list, the validation fails.↵↵Secondly, in order to prevent UTXOs from being double-used, the Bitcoin network introduces the concept of timestamps. When a user attempts to spend a UTXO, they must include a timestamp in the transaction. The timestamp ensures that the UTXO is not spent before the specified period has passed. If the transaction does not include a valid timestamp or the timestamp has passed, the transaction will be rejected by the network"}]}],"pr":"91f2985094ce64c923443eb202d44d769e416d1a2d6f62bfe0251415104795b4"}