full-stack-ethereum/contracts/Greeter.sol

//SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

contract Greeter {
  string greeting;

  constructor(string memory _greeting) {
    greeting = _greeting;
  }

  function greet() public view returns (string memory) {
    return greeting;
  }

  function setGreeting(string memory _greeting) public {
    greeting = _greeting;
  }
}