Variable Types + Visibility

Variables.sol

pragma solidity >=0.5.0 <0.7.0;

contract Test {
    
    // Variable Example
    // Unsigned integer that is visibile to derived contracts equal to 10
    uint256 internal _demoOne = 10;
    // boolean equal to true that is visible to everyone
    bool public _demoTwo = true;

    // Arrays & Mapping Example
    // Mapping (like objects/dictionaries/etc) from address to integer
    mapping (address => uint) public _demoMapping;
    // Array of addresses (can be an array of any variable type)
    address[] public _demoArray;

    // ------------ MISSION OBJECTIVES ----------------------
    // Create the following:
    // integer equal to 10 that is visible to internal and external contracts
    // boolean equal to true that is only visible to itself
    // address equal to 0x15fd1E4F13502b1a8BE110F100EC001d0270552d that is visible to everyone
    uint256 _int;
    bool _bool;
    address _address;

    // Create the following:
    // a mapping from integer to bool
    // an array of booleans
    public _mapping;
    public _boolArray = [false, true];

    // ------------------------------------------------------
    // DO NOT MODIFY BELOW - USED FOR TESTING
    function test() public returns (bool) {
        _mapping[100] = true;

        require(_int == 10, "Integer correct");
        require(_bool == true, "Boolean correct");
        require(_address == 0x15fd1E4F13502b1a8BE110F100EC001d0270552d, "Address correct");
        require(_mapping[100] == true, "Mapping correct");
        require(_boolArray[1] == true, "Array correct");
        return true;
    }
}