Excuse me, but could you please clarify for me which of the following would not be considered an exchange transaction in the context of cryptocurrency and finance? Is it the buying and selling of digital currencies on a centralized platform, the peer-to-peer transfer of coins between individuals, the swapping of tokens within a decentralized exchange, or perhaps the mining of new coins through solving complex algorithms? I'm interested in understanding which activity doesn't fall under the umbrella of exchange transactions in this field.