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ballot.sol

pragma solidity >=0.4.22 <0.6.0;
contract Ballot {

    struct Voter {
        uint weight;
        bool voted;
        uint8 vote;
        address delegate;
    }
    struct Proposal {
        uint voteCount;
    }

    address chairperson;
    mapping(address => Voter) voters;
    Proposal[] proposals;

    /// Create a new ballot with $(_numProposals) different proposals.
    constructor(uint8 _numProposals) public {
        chairperson = msg.sender;
        voters[chairperson].weight = 1;
        proposals.length = _numProposals;
    }

    /// Give $(toVoter) the right to vote on this ballot.
    /// May only be called by $(chairperson).
    function giveRightToVote(address toVoter) public {
        if (msg.sender != chairperson || voters[toVoter].voted) return;
        voters[toVoter].weight = 1;
    }

    /// Delegate your vote to the voter $(to).
    function delegate(address to) public {
        Voter storage sender = voters[msg.sender]; // assigns reference
        if (sender.voted) return;
        while (voters[to].delegate != address(0) && voters[to].delegate != msg.sender)
            to = voters[to].delegate;
        if (to == msg.sender) return;
        sender.voted = true;
        sender.delegate = to;
        Voter storage delegateTo = voters[to];
        if (delegateTo.voted)
            proposals[delegateTo.vote].voteCount += sender.weight;
        else
            delegateTo.weight += sender.weight;
    }

    /// 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 view 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;
            }
    }
}

ballot_test.sol

import "remix_tests.sol"; // this import is automatically injected by Remix.
import "./ballot.sol";

contract test3 {
   
    Ballot ballotToTest;
    function beforeAll () public {
       ballotToTest = new Ballot(2);
    }
    
    function checkWinningProposal () public {
        ballotToTest.vote(1);
        Assert.equal(ballotToTest.winningProposal(), uint(1), "1 should be the winning proposal");
    }
    
    function checkWinninProposalWithReturnValue () public view returns (bool) {
        return ballotToTest.winningProposal() == 1;
    }
}

ConfirmaV1.sol

contract ConfirmaV1 {
    
    struct Contrato {
      string nroContrato;
      uint comprador;
      uint corredor;
      uint vendedor;
    }  
    
     mapping (address => Contrato) contratoStruct;
     
     address[] public contratos; 
     
     address owner;
     
     constructor() public { owner = msg.sender; }
     
     function createUserByVendedor(string nroContrato, uint comprador, uint vendedor) {
  
      contratoStruct[msg.sender].comprador = comprador;
      contratoStruct[msg.sender].vendedor = vendedor;
      contratoStruct[msg.sender].nroContrato = nroContrato;
      
      contratos.push(msg.sender);
    }
    
    function getAllContratos() external view returns (address[]) {
      return contratos;
    }
    
    function getContrato(address _address) view public returns (string, uint, uint) {
        return (contratoStruct[_address].nroContrato, contratoStruct[_address].comprador, contratoStruct[_address].vendedor);
    }
    
    
}

ConfirmaV2.sol

contract ConfirmaV2 {
    
    struct Contrato {
      string nroContrato;
      uint comprador;
      uint corredor;
      uint vendedor;
      bool firmadoComprador;
      bool firmadoVendedor;
    }  
    
     mapping (string => Contrato) contratoStruct;
     
     string[] public contratos; 
     
     address owner;
     
     constructor() public { owner = msg.sender; }
     
     function createContrato(string nroContrato, uint comprador, uint vendedor) {
  
      contratoStruct[nroContrato].comprador = comprador;
      contratoStruct[nroContrato].vendedor = vendedor;
      contratoStruct[nroContrato].nroContrato = nroContrato;
      contratoStruct[nroContrato].firmadoComprador = false;
      contratoStruct[nroContrato].firmadoVendedor = false;
      
      contratos.push(nroContrato);
    }
    
    function firmarComprador(string nroContrato, uint comprador) {
        if (contratoStruct[nroContrato].comprador == comprador)
            contratoStruct[nroContrato].firmadoComprador = true;
    }
    
    function firmarVendedor(string nroContrato, uint vendedor) {
        if (contratoStruct[nroContrato].vendedor == vendedor)
            contratoStruct[nroContrato].firmadoVendedor = true;
    }
    
    function getContrato(string _address) view public returns (string, uint, uint) {
        return (contratoStruct[_address].nroContrato, contratoStruct[_address].comprador, contratoStruct[_address].vendedor);
    }
    
    
}

KeyValueStorage.sol

contract KeyValueStorage {

  mapping(address => mapping(bytes32 => uint256)) _uintStorage;
  mapping(address => mapping(bytes32 => address)) _addressStorage;
  mapping(address => mapping(bytes32 => bool)) _boolStorage;

  /**** Get Methods ***********/

  function getAddress(bytes32 key) public view returns (address) {
      return _addressStorage[msg.sender][key];
  }

  function getUint(bytes32 key) public view returns (uint) {
      return _uintStorage[msg.sender][key];
  }

  function getBool(bytes32 key) public view returns (bool) {
      return _boolStorage[msg.sender][key];
  }

  /**** Set Methods ***********/

  function setAddress(bytes32 key, address value) public {
    _addressStorage[msg.sender][key] = value;
  }

  function setUint(bytes32 key, uint value) public {
      _uintStorage[msg.sender][key] = value;
  }

  function setBool(bytes32 key, bool value) public {
      _boolStorage[msg.sender][key] = value;
  }

}

SmartContratSolidityHelloWorld.sol

contract HelloWorld {

 uint256 counter = 5;
 
 address owner = msg.sender; //set owner as msg.sender
 
 function add() public {  //increases counter by 1
  counter++;
 }
 
 function subtract() public { //decreases counter by 1
  counter--;
 }
 
 function getCounter() public constant returns (uint256) {
  return counter;
 } 
 
 function kill() public { //self-destruct function, 
   if(msg.sender == owner) {
    selfdestruct(owner); 
    }
 }
 
 function () public payable {
 
 }
 
}

Users.sol

contract Users {

    struct User {
      string name;
      uint level;
    }    

    mapping (address => User) userStructs;

    address[] public userAddresses;
    
    function createUser(string name, uint level) {
  
      // set User name using our userStructs mapping
      userStructs[msg.sender].name = name;
      // set User level using our userStructs mapping
      userStructs[msg.sender].level = level;
      // push user address into userAddresses array
      userAddresses.push(msg.sender);
    }

    function getAllUsers() external view returns (address[]) {
      return userAddresses;
    }
    
}

voting.sol

pragma solidity ^0.4.18;

contract voting {

  mapping (bytes32 => uint8) public votesReceived;

  /* Solidity doesn't let you pass in an array of strings in the constructor.
  Using an array of bytes32 instead to store the list of candidates
  */

  bytes32[] public candidateList;

  //This is the constructor and is called once you deploy the contract
  function voting(bytes32[] candidateNames) public {
    candidateList = candidateNames;
  }

  // Returns the total votes a candidate has received
  function totalVotesFor(bytes32 candidate) view public returns (uint8) {
    require(validCandidate(candidate));
    return votesReceived[candidate];
  }

  // Increments the vote count for the specified candidate
  function voteForCandidate(bytes32 candidate) public {
    require(validCandidate(candidate));
    votesReceived[candidate] += 1;
  }

  function validCandidate(bytes32 candidate) view public returns (bool) {
    for(uint i = 0; i < candidateList.length; i++) {
      if (candidateList[i] == candidate) {
        return true;
      }
    }
    return false;
  }
}