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t.sol

pragma solidity ^0.4.24;
library SafeMath {

  /**
  * @dev Multiplies two numbers, throws on overflow.
  */
  function mul(uint256 a, uint256 b) internal pure returns (uint256 c) {
    // Gas optimization: this is cheaper than asserting 'a' not being zero, but the
    // benefit is lost if 'b' is also tested.
    // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
    if (a == 0) {
      return 0;
    }

    c = a * b;
    assert(c / a == b);
    return c;
  }

  /**
  * @dev Integer division of two numbers, truncating the quotient.
  */
  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 a / b;
  }

  /**
  * @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
  */
  function sub(uint256 a, uint256 b) internal pure returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  /**
  * @dev Adds two numbers, throws on overflow.
  */
  function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
    c = a + b;
    assert(c >= a);
    return c;
  }
}
contract Ownable {
  address public owner;


  event OwnershipRenounced(address indexed previousOwner);
  event OwnershipTransferred(
    address indexed previousOwner,
    address indexed newOwner
  );


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  constructor() 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 relinquish control of the contract.
   * @notice Renouncing to ownership will leave the contract without an owner.
   * It will not be possible to call the functions with the `onlyOwner`
   * modifier anymore.
   */
  function renounceOwnership() public onlyOwner {
    emit OwnershipRenounced(owner);
    owner = address(0);
  }

  /**
   * @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 {
    _transferOwnership(_newOwner);
  }

  /**
   * @dev Transfers control of the contract to a newOwner.
   * @param _newOwner The address to transfer ownership to.
   */
  function _transferOwnership(address _newOwner) internal {
    require(_newOwner != address(0));
    emit OwnershipTransferred(owner, _newOwner);
    owner = _newOwner;
  }
}
contract Savemylife is Ownable{
    event SendEth(uint256 id,address from,uint256 amount);
    event ReturnEth(uint256 id,address from,uint256 amount);
    event Saveme(uint256 id,address owner,uint256 amount);
    event Start(uint256 id,address owner,uint256 totalBalance,uint256 endtime);
    event Active(uint256 id);
    event Stop(uint256 id);
    event NotStop(uint256 id);
    
    
    struct Balances {
        address addr;
        uint256 amount;
    }
    struct ICO {
        address owner; //发起人
        uint256 totalBalance; //一共需要多少钱 
        uint256 balance; //当前余额
        uint256 canUserAmount;//可用的钱 
        uint256 endtime; //ICO 结束时间 
        uint256 id;
        bool status; //状态 
        bool stop;
        mapping(uint256 => Balances) balances; // 捐款详情 
    }
    using SafeMath for uint256;
    uint256 public icoid;
    mapping (uint256 => ICO) public ico;
    
    function start (uint256 totalBalance,uint256 endtime) public{
       icoid = icoid.add(1);
       ico[icoid] = ICO(msg.sender,totalBalance,0,0,endtime,0,false,false);
       emit Start(icoid,msg.sender,totalBalance,endtime);
    }
    
    function sendEth(uint256 id) payable public {
        require(isActive(id));
        require(notStop(id));
        ICO storage c = ico[id];
        require(c.endtime>now);
        uint256 _totalBalance = c.balance.add(msg.value);
        uint256 send = msg.value;
        if (_totalBalance > c.totalBalance){
            uint256 ret = _totalBalance.sub(c.totalBalance);
            msg.sender.transfer(ret);
            emit ReturnEth(id,msg.sender,ret);
            c.status = false;
            c.balance = c.totalBalance;
            send = msg.value.sub(ret);
        }else{
            c.balance = c.balance.add(send);
        }
        // c.balances[msg.sender] = msg.value;
        c.id = c.id.add(1);
        
        c.canUserAmount = c.canUserAmount.add(send);
        c.balances[c.id] = Balances({addr: msg.sender, amount: send});
        emit SendEth(id,msg.sender,send);
    
    }
    
    function safeWithdrawl(uint256 id,uint256 amount) public returns (bool){
        require(isIcoOwner(id));
        require(notStop(id));
        ICO storage c = ico[id];
        uint256 canWithdrawAmout = c.canUserAmount;
        require(amount <= canWithdrawAmout);
        msg.sender.transfer(amount);
        emit Saveme(id,msg.sender,amount);
        c.canUserAmount = c.canUserAmount.sub(amount);
    }
    
    function getBalance(uint256 icoid,uint256 id) view public {
        ICO storage c = ico[icoid];
       //todo: 返回每个ICO的捐款情况  
    }
    constructor () public {
        start(10 ether,1632173131);
    } 
    
    function active(uint256 id) onlyOwner public {
        require(!isActive(id));
        ICO storage c = ico[id];
        c.status = true;
        emit Active(id);
    }
    
    function isActive(uint256 id) view public returns (bool status){
        require(id<=icoid);
        ICO storage c = ico[id];
        return c.status;
    }
    
    function isIcoOwner(uint256 id) view public returns (bool status){
        require(id<=icoid);
        ICO storage c = ico[id];
        return msg.sender == c.owner;
    }
    function notStop(uint256 id) view public returns (bool){
        ICO storage c = ico[id];
        return c.stop == false;
    }
    
    
    function stop(uint256 id) onlyOwner public {
        require(notStop(id));
        ICO storage c = ico[id];
        c.stop = true;
        emit Stop(id);
    }
    function notstop(uint256 id) onlyOwner public {
        require(!notStop(id));
        ICO storage c = ico[id];
        c.stop = false;
        emit NotStop(id);
    }
    
}