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commitment.sol

pragma solidity ^0.4.0;

contract Commitment {
    enum CommitmentState { OPEN, CLOSED }
    
    mapping (address => bool) attendeesRegistered;
    mapping (address => bool) attendeesRefunded;
    
    uint totalDeposited;
    uint totalGuests;
    uint public depositAmount;
    CommitmentState public currentState;
    function Commitment(uint _depositAmount) {
        depositAmount = _depositAmount;
        currentState = CommitmentState.OPEN;
    }
    
    function addAttendee() payable {
        require(msg.value >= depositAmount);
        require(currentState == CommitmentState.OPEN);
        require(!attendeesRegistered[msg.sender]);
        
        totalDeposited += msg.value;
        totalGuests += 1;
        attendeesRegistered[msg.sender] = true;
    }
}