text: const clone = require('clone')
  
  module.exports = (state, action) => {
    const { type, payload } = action
    const newState = clone(state)
    const { counterValues } = newState
    switch (type) {
      case 'ADD_COUNTER':
        counterValues.push(0)
        return newState
      case 'INCREMENT':
        counterValues[payload] +=  1
        return newState
      case 'DECREMENT':
        counterValues[payload] -=  1
        return newState
      default:
        return newState
    }
  }
  