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HashStorage.sol

pragma solidity ^0.4.24;

contract HashStorage{
    
    mapping(address => bytes32[]) hashes;
    mapping(string => bytes32) tagsToHash;
    
    function write(bytes32 _hash, string tags) public{
        /*TODO: add requires*/
        hashes[msg.sender].push(_hash);
        tagsToHash[tags] = _hash;
    }
    
    function getHashes() public view returns(bytes32[]){
        return hashes[msg.sender];
    }
    
    function getHashByTag(string tag) public view returns(bytes32){
        return tagsToHash[tag];
    }
    
}