smart contract

mail.sol

pragma solidity ^0.4.8;

contract Charity {
    address owner;
    address boardMember1;
    address boardMember2;
    address recipient;
    bool registeredYet;
    mapping(address => bool) signatures;
    
    struct Donation {
      address donor;
      uint value;
    }
    
    Donation[] donations;
    
    function Charity() {
        owner = msg.sender;
        registeredYet = false;
    }

    function addBoardMembers(address bm1, address bm2) returns (string) {
        if (msg.sender == owner && !registeredYet) {
            boardMember1 = bm1;
            boardMember2 = bm2;
            registeredYet = true;
        }
        else if (registeredYet) {
            return 'already registered';
        }
        else return 'not owner';
    }
    
    function donate() payable returns (string) {
        donations.push(Donation(msg.sender, msg.value));
    }
    
    function addSignature() returns (string) {
        if (msg.sender == owner) {
            signatures[owner] = true;
        }
        else if (msg.sender == boardMember2) {
            signatures[boardMember2] = true;
            
        }
        else if (msg.sender == boardMember1) {
            signatures[boardMember1] = true;
        }
    }
    
    function addRecipient(address recip) returns (string) {
        if (msg.sender == owner) {
            recipient = recip;
            return 'thanks';
        }
    }
    
    function withdraw() returns (string) {
        if (msg.sender == boardMember1 || msg.sender == boardMember2) {
            uint numSignatures = 0;
            if (signatures[owner] == true || 
            signatures[boardMember2] == true || 
            signatures[boardMember1] == true) {
                numSignatures++;
            }
        }
        
        if (numSignatures >=2) {
            recipient.send(this.balance);
        }
        
        
        
        
    }
}