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                <div id="root"></div>




                import React from "[email protected]";
import ReactDOM from "[email protected]";
import redux from "[email protected]";
import { configureStore, createSlice } from "[email protected]";
import { Provider, useSelector, useDispatch } from "[email protected]";

const initialState = {
  value: 0,

const counterSlice = createSlice({
  name: 'counter',
  // Редьюсеры в слайсах мутируют состояние и ничего не возвращают наружу
  reducers: {
    increment: (state) => {
      state.value += 1;
    decrement: (state) => {
      state.value -= 1
    // пример с данными
    incrementByAmount: (state, action) => {
      state.value += action.payload
const { increment, decrement, incrementByAmount } = counterSlice.actions;

const counterReducer = counterSlice.reducer;

const store = configureStore({
  reducer: {
    // counter – имя внутри объекта состояния state.counter
    counter: counterReducer,

const App = () => {
  // Вытаскиваем данные из хранилища. state – все состояние
  const count = useSelector((state) => state.counter.value);
  // Возвращает метод store.dispatch() текущего хранилища
  const dispatch = useDispatch();

  return (
          aria-label="Increment value"
          onClick={() => dispatch(increment())}
          aria-label="Decrement value"
          onClick={() => dispatch(decrement())}
        <br />
        <button onClick={() => dispatch(incrementByAmount(42))}>Прибавить 42</button>

  <Provider store={store}>
    <App />