迪斯克质押众筹模式系统开发

　　区块链智能合约是一种基于区块链技术的自动化合约。開发+l8l-案例259l-系统3365微電它是一种能够自动执行合约条款、不需要人类介入而能够保证执行结果的计算机程序。智能合约实际上是一段可编程的代码，这段代码会被上传到区块链上，并在区块链中被运行，以实现合约所预期的功能。这样，同样的代码逻辑可以被多方审计和验证，从而保证各方的利益得以大化。

　　智能合约隶属于区块链技术的智能合约系统，它包含了一系列的分布式账本（区块链）以及对这个分布式账本进行的操作过程。智能合约的主要特点是：去中心化、透明性、不可篡改性以及不可撤销性。因此，智能合约具有高度的安全性和准确性，能够确保交易的顺利完成。

/**
*Submitted for verification at Ethe*** on 2017-11-28
*/

pragma solidity ^0.4.17;

/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
  function mul(uint256 a, uint256 b) internal pure returns (uint256) {
    if (a == 0) {
        return 0;
    }
    uint256 c = a * b;
    assert(c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal pure returns (uint256) {
    // assert(b > 0); // Solidity automatically throws when dividing by 0
    uint256 c = a / b;
    // assert(a == b * c + a % b); // There is no case in which this doesn't hold
    return c;
  }

  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal pure returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
  address public owner;

  /**
    * @dev The Ownable constructor sets the original `owner` of the contract to the sender
    * account.
    */
  function Ownable() public {
    owner = msg.sender;
  }

  /**
    * @dev Throws if called by any account other than the owner.
    */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }

  /**
  * @dev Allows the current owner to transfer control of the contract to a newOwner.
  * @param newOwner The address to transfer ownership to.
  */
  function transferOwnership(address newOwner) public onlyOwner {
    if (newOwner != address(0)) {
        owner = newOwner;
    }
  }

}

/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://g***/ethereum/EIPs/issues/20
*/
contract ERC20Basic {
  uint public _totalSupply;
  function totalSupply() public constant returns (uint);
  function balanceOf(address who) public constant returns (uint);
  function transfer(address to, uint value) public;
  event Transfer(address indexed from, address indexed to, uint value);
}