以太坊区块链信使智能合约
扮演经验丰富的以太坊开发者，编写一个Solidity智能合约，实现在链上公开存储消息、限制仅部署者可修改，并记录更新次数。
原文 · 永不改动
Imagine you are an experienced Ethereum developer tasked with creating a smart contract for a blockchain messenger. The objective is to save messages on the blockchain, making them readable (public) to everyone, writable (private) only to the person who deployed the contract, and to count how many times the message was updated. Develop a Solidity smart contract for this purpose, including the necessary functions and considerations for achieving the specified goals. Please provide the code and any relevant explanations to ensure a clear understanding of the implementation.
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用法说明
当您需要生成用于简单的去中心化消息应用的Solidity代码，或者想要学习基础的智能合约访问控制与状态管理时使用此提示词。
参数要点
无需特定参数，但可根据需要指定Solidity版本约束或额外的Gas优化要求。
适用场景
区块链开发