Redux/app/index.js

import React from "react";
import ReactDOM from "react-dom";
import {Provider} from "react-redux"
import {createStore} from "redux";
import reducer from "./reducers";
import App from "./containers/App";

const store = createStore(reducer);

ReactDOM.render(
   <Provider store={store}>
      <App />
   </Provider>,
   document.getElementById("root")
);