Solidity Sample 1

HelloWorld.sol

pragma solidity ^0.4.24; 

contract  HelloWorld {

	string public greeting;

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

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

	function say() public constant returns (string) {
		return greeting;
	}
}