Learning Solidity Contracts

Lottery2.sol

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.7.0 <0.9.0;

contract Lottery {
    
    address public manager;
    address[] public players;
    
    
    constructor() {
        manager = msg.sender;
    }
    
    function enter() public payable {
       
        
        require(msg.value > .01 ether);
        players.push(msg.sender);
    }
    
    function pickWinner() public payable restricted {
        //require(msg.sender == manager);
         
        uint index = random() % players.length;
        payable(players[index]).transfer(address(this).balance);
        
        // Reset the array 
        players = new address[](0);
    }
    
    function random() private view returns (uint) {
        
        return uint(keccak256(abi.encodePacked(block.difficulty,block.timestamp, players)));
        
        
    }
    
    modifier restricted() {
        require(msg.sender == manager);
        _;
    }
    
    function getPlayers() public view returns (address[] memory) {
        return players;
    }
    
    
    
    
    
}