Voting_Homework/Voting hazi.sol

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.11;


contract VoteforBest {
    uint public NFT;
    uint public ERC20;
    uint public DAO;
    mapping(address => bool) private Voters;
   


    struct Voter{
        bool voteSpent;
        uint weight;
    }

    struct Proposal{
        uint votenumber;
    }

    address public chairman;

    mapping(address => Voter ) public voters;



    function Vote (string memory _choice) public {
    chairman = msg.sender;
    Voter storage sender = voters[msg.sender];
    require(!sender.voteSpent, 'Please do not vote more than once');
    voters[chairman].weight = 1;
    sender.voteSpent = true;
    if (keccak256(abi.encodePacked(_choice)) == keccak256(abi.encodePacked("NFT"))) {
        NFT++;}
    else if (keccak256(abi.encodePacked(_choice)) == keccak256(abi.encodePacked("DAO"))) {
        DAO++;}
    else {
        require(keccak256(abi.encodePacked(_choice)) == keccak256(abi.encodePacked("ERC20")), 'Please use valid vote option');
        ERC20++;
    }}

    function showstatus () public view returns (uint NFT_, uint ERC20_, uint DAO_){
        return (NFT, ERC20, DAO);
    }

    function Winner () public view returns (string memory){
        if (NFT>ERC20 && NFT>DAO) {
            return "NFT";}
        else if (ERC20 > NFT && ERC20 > DAO) {
            return "ERC20";}
        else if (DAO > NFT && DAO > ERC20) {
            return "DAO";}

        return "No winner";       
    }

    
}