js数组格式转换问题

Question

如何将上面这个数据，转换成下面这种，初学者，表示好难，还请各位老哥答疑解惑
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Answer 1

编辑一下，建议题主下次贴代码，不要放截图，谢谢。

arr.reduce((acc, cur) => {
  const { year, month } = cur;

  let targetYearObj = acc.find((item) => item.year === year);
  if (!targetYearObj) {
    targetYearObj = { year, list: [] };
    acc.push(targetYearObj);
  }

  let targetMonthObj = targetYearObj.list.find((item) => item.month === month);
  if (!targetMonthObj) {
    targetMonthObj = { month, children: [] };
    targetYearObj.list.push(targetMonthObj);
  };

  targetMonthObj.children.push(cur);
  return acc;
}, []);