QuickStart 솔리디티 예제 연습 코드 #1

quickstart-exam.sol

pragma solidity ^0.4.17;

contract Compaign {
    struct Request {
        string description;
        uint value;
        address recipient;
        bool complete;
        uint approvalCount;
        mapping(address => bool) approvals;
    }
    
    Request[] public requests;
    address public manager;
    uint public minimumContribution;
    mapping(address => bool) public approvers;
    uint public approversCount;
    
    modifier restricted() {
        require(msg.sender == manager);
        _;
    }
    
    function Compaign(uint minimum) public {
        manager = msg.sender;
        minimumContribution = minimum;
    }
    
    function contribute() public payable {
        require(msg.value > minimumContribution);
        
        approvers[msg.sender] = true;
        approversCount++;
    }
    
    function createRequest(string description, uint value, address recipient) 
        public restricted 
    {
       require(approvers[msg.sender]);
       
       Request memory newRequest = Request({
           description: description,
           value: value,
           recipient: recipient,
           complete: false,
           approvalCount: 0
       });   
       
       
       requests.push(newRequest);
    }
    
    function approveRequest(uint index) public {
        Request storage request = requests[index];
        
        require(approvers[msg.sender]);
        require(!request.approvals[msg.sender]);
        
        request.approvals[msg.sender] = true;
        request.approvalCount++;
    }
}