A <Router> may have only one child element

<BrowserRouter>
      <Route path="/" component={App} />
      <Route path="/01" component={Record} />
  </BrowserRouter>
<BrowserRouter>
  <div>
      <Route path="/" component={App} />
      <Route path="/01" component={Record} />
  </div>
</BrowserRouter>

A <Router> may have only one child element