C++ hash in #include <unordered_map>

#pragma once
#pragma comment(lib,"rpcrt4.lib")

#include <Windows.h>
#include <rpcdce.h>
#include <iostream>
#include <thread>
#include <unordered_map>

using namespace std;

string getUuid()
{
    RPC_CSTR rpcCstr;
    string uuidValue;
    UUID newUUID;
    UuidCreate(&newUUID);
    UuidToStringA(&newUUID, &rpcCstr);
    uuidValue = (char*)rpcCstr;
    RpcStringFreeA(&rpcCstr);
    return uuidValue;
}
 
void hashDemo()
{
    string uuid = getUuid();
    size_t hash = std::hash <string>{}(uuid);
    cout << "Uuid=" << uuid << endl;
    cout << "Hash=" << hash << endl;
}

int main(int args, char** argv)
{
    hashDemo();
}