A multi signatory smart contract for sending funds on the block chain

MultiSigWallet.sol

pragma solidity ^0.4.0;
pragma experimental ABIEncoderV2;

contract MultiSigWallet {
    uint minApprovers;
    
    address beneficiary;
    address owner;
    
    mapping(address => bool) approvedBy;
    mapping(address => bool) isApprover;
    
    uint approvalsNum;
    
    constructor(address _beneficiary, uint _minApprovers, address[] _approvers) public payable {
        require(_minApprovers <= _approvers.length, "Required number of approvers should be less than number of approvers");
        
        minApprovers = _minApprovers;
        beneficiary = _beneficiary;
        owner = msg.sender;
        
        for (uint i = 0; i < _approvers.length; i++) {
            address approver = _approvers[i];
            isApprover[approver] = true;
        }
    }
    
    function approve() public {
         require(isApprover[msg.sender], 'Not an approver');
         if (!approvedBy[msg.sender]) {
             approvalsNum++;
             approvedBy[msg.sender] = true;
         }
         
         if (approvalsNum == minApprovers) {
             beneficiary.send(address(this).balance);
             selfdestruct(owner);
         }
    }
    
    function reject() public {
        require(isApprover[msg.sender], 'Not an approver');
        selfdestruct(owner);
    }
}