pragma solidity >=0.4.22 <0.6.0;

contract A {

    event eSet(string _a);

    string a;

    constructor() public {}

    function setA(string memory _a) public {
        a = _a;
        emit eSet(a);
    }

    function getA() external view returns (string memory _a) {
        return a;
    }
}