const tree = {
  val: 'a',
  children: [
    {
      val: 'b',
      children: [
        {
          val: 'd',
          children: [
            {
              val: 'h',
              children: [],
            },
            {
              val: 'i',
              children: [],
            },
          ],
        },
        {
          val: 'e',
          children: [
            {
              val: 'j',
              children: [],
            },
            {
              val: 'k',
              children: [],
            },
          ],
        },
      ],
    },
    {
      val: 'c',
      children: [
        {
          val: 'f',
          children: [
            {
              val: 'l',
              children: [],
            },
            {
              val: 'm',
              children: [],
            },
          ],
        },
        {
          val: 'g',
          children: [
            {
              val: 'n',
              children: [],
            },
            {
              val: 'o',
              children: [],
            },
          ],
        },
      ],
    },
  ],
};

求教老师，这个数据结构，能否用递归的方式去做广度优先遍历？我想了好久都没想出来

用队列是我是OK的，队列就适合这种明确有序的遍历