Simple redux working

Redux-basic.js

const redux = require('redux')
const createStore = redux.createStore;

const initialState = {
    counter : 0
}

// reducer
const rootReducer = (state = initialState,action) => {
    if (action.type === 'INC_COUNTER') {
        return {
            ...state,
            counter: state.counter + 1
        }
    }
    if (action.type === 'ADD_COUNTER') {
        return {
            ...state,
            counter: state.counter + action.value
        }
    }
    return state;
}

//store 
const store = createStore(rootReducer);
console.log(store.getState());

//subscription
store.subscribe(()=>{
    console.log('[subscription]',store.getState()); 
})

//dispatching action
store.dispatch({type:'INC_COUNTER'});
store.dispatch({type:'ADD_COUNTER', value:10});
console.log(store.getState());