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contacts.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.20;

import "@openzeppelin/contracts/access/Ownable.sol";

contract ContactManager is Ownable {
    constructor(address initialOwner) Ownable(initialOwner) {}

    struct User {
        address userAddress;
        string[] hashes;
    }

    User[] public users;
    mapping(address => uint) public userIndex;

    function createUser() public {
        users.push(User({
            userAddress: msg.sender,
            hashes: new string[](0)
        }));
        userIndex[msg.sender] = users.length - 1;
    }

    function addUserHash(string memory _hash) public {
        uint index = userIndex[msg.sender];
        users[index].hashes.push(_hash);
    }

    function removeUserHash(uint _index) public {
        uint userIndex_ = userIndex[msg.sender];
        User storage user = users[userIndex_];
        user.hashes[_index] = user.hashes[user.hashes.length - 1];
        user.hashes.pop();
    }

    function getUserHashes() public view returns (string[] memory) {
        uint index = userIndex[msg.sender];
        return users[index].hashes;
    }

    function removeUser() public {
        
    }
}