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messenger.sol

pragma solidity ^0.4.24;

contract Messenger{
    address owner;
    string[] messages;
    
    constructor() public{
        owner = msg.sender;
    }
    
    function add(string memory newMessage) public{
        require(msg.sender == owner);
        messages.push(newMessage);
        
    }
    
    function count() view public returns(uint){
        return messages.length;
    }
    
    function getMessages(uint index) view public returns(string){
        return messages[index];
        
    }
}