// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.8.2 <0.9.0;


contract SimpleStorage {
    uint storedData;

    function set(uint x) public {
        storedData = x;
    }

    function get() public view returns (uint) {
        return storedData;
    }

    function get_private() public view returns (uint) {
        return not_get();
    }

    function not_get() private view returns (uint) {
        return storedData;
    }
}

contract StorageExtended {

   address private owner;

    event OwnerSet(address indexed oldOwner, address indexed newOwner);

    modifier isOwner() {
        require(msg.sender == owner, "Caller is not owner");
        _;
    }

    // SPoF
    constructor() {
        owner = msg.sender;
        emit OwnerSet(address(0), owner);
    }

    function changeOwner(address newOwner) public isOwner {
        emit OwnerSet(owner, newOwner);
        owner = newOwner;
    }

    function getOwner() external view returns (address) {
        return owner;
    }


    uint256 number;

    function store(uint256 num) public {
        number = num;
    }

    function retrieve() public view returns (uint256){
        return number;
    }
}