// 定义原始数据列表
const data = [
  {
    id: 1,
    name: '苹果',
    category: '水果',
    children: [
      {
        id: 11,
        name: '红富士',
        category: '水果',
        children: []
      },
      {
        id: 12,
        name: '青苹果',
        category: '水果',
        children: []
      }
    ]
  },
  {
    id: 2,
    name: '茄子',
    category: '蔬菜',
    children: []
  },
  {
    id: 3,
    name: '鲫鱼',
    category: '水产',
    children: []
  },
  {
    id: 4,
    name: '白菜',
    category: '蔬菜',
    children: [
      {
        id: 41,
        name: '老白菜',
        category: '蔬菜',
        children: []
      }
    ]
  }
]

// 定义分类统计函数
function countByCategory(data) {
  const result = {}
  data.forEach(item => {
    if (!result[item.category]) {
      result[item.category] = 1
    } else {
      result[item.category] += 1
    }
    if (item.children) {
      Object.assign(result, countByCategory(item.children))
    }
  })
  return result
}

// 调用分类统计函数
const countResult = countByCategory(data)
console.log(countResult)
// 输出结果：{ '水果': 3, '蔬菜': 3, '水产': 1 }