pragma solidity ^0.4.0; contract Ballot { struct Voter { uint weight; bool voted; uint8 vote; // address delegate; } struct Proposal { uint voteCount; // could add other data about proposal } address chairperson; mapping(address => Voter) voters; Proposal[] proposals; /// Create a new ballot with $(_numProposals) different proposals. function Ballot(uint8 _numProposals) public { chairperson = msg.sender; voters[chairperson].weight = 2; proposals.length = _numProposals; } /// Give $(toVoter) the right to vote on this ballot. /// May only be called by $(chairperson). function register(address toVoter) public { if (msg.sender != chairperson || voters[toVoter].voted) return; voters[toVoter].weight = 1; voters[toVoter].voted = false; } /// Give a single vote to proposal $(toProposal). function vote(uint8 toProposal) public { Voter storage sender = voters[msg.sender]; if (sender.voted || toProposal >= proposals.length) return; sender.voted = true; sender.vote = toProposal; proposals[toProposal].voteCount += sender.weight; } function winningProposal() public constant returns (uint8 _winningProposal) { uint256 winningVoteCount = 0; for (uint8 prop = 0; prop < proposals.length; prop++) if (proposals[prop].voteCount > winningVoteCount) { winningVoteCount = proposals[prop].voteCount; _winningProposal = prop; } } }