Voting Contract

Voting.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

contract Voting {
    struct Candidate {
        string name;
        uint256 voteCount;
    }

    Candidate[] public candidates;
    mapping(address => bool) public voters;

    address public owner;

    constructor(string[] memory candidateNames) {
        owner = msg.sender;
        
        for (uint i = 0; i < candidateNames.length; i++) {
            candidates.push(Candidate({
                name: candidateNames[i],
                voteCount: 0
            }));
        }
    }

    modifier onlyOwner() {
        require(msg.sender == owner, "Only the owner can call this function");
        _;
    }

    function vote(uint256 candidateIndex) public {
        require(!voters[msg.sender], "You have already voted");
        require(candidateIndex < candidates.length, "Invalid candidate index");

        voters[msg.sender] = true;
        candidates[candidateIndex].voteCount++;
    }

    function getCandidateCount() public view returns (uint256) {
        return candidates.length;
    }

    function getCandidate(uint256 index) public view returns (string memory, uint256) {
        require(index < candidates.length, "Invalid candidate index");
        Candidate memory candidate = candidates[index];
        return (candidate.name, candidate.voteCount);
    }

    function getCandidates(uint256[] memory indices) public view returns (string[] memory names, uint256[] memory voteCounts) {
        names = new string[](indices.length);
        voteCounts = new uint256[](indices.length);

        for (uint256 i = 0; i < indices.length; i++) {
            require(indices[i] < candidates.length, "Invalid candidate index");
            Candidate memory candidate = candidates[indices[i]];
            names[i] = candidate.name;
            voteCounts[i] = candidate.voteCount;
        }

        return (names, voteCounts);
    }

    function getWinner() public view returns (string memory, uint256) {
        require(candidates.length > 0, "No candidates available");

        uint256 winningVoteCount = 0;
        uint256 winningCandidateIndex = 0;

        for (uint256 i = 0; i < candidates.length; i++) {
            if (candidates[i].voteCount > winningVoteCount) {
                winningVoteCount = candidates[i].voteCount;
                winningCandidateIndex = i;
            }
        }

        return (candidates[winningCandidateIndex].name, winningVoteCount);
    }
}