[javascript] flatmap

  const aaa = classroom?.students.map((student) =>
    student.reviews
      .filter((review) => review.project.id === projectId && review.isDraft === true)
      .map((review) => review.student.id)
  )
  
    const bbb = classroom?.students.flatMap((student) =>
    student.reviews
      .filter((review) => review.project.id === projectId && review.isDraft === true)
      .map((review) => review.student.id)
  )

  console.log(aaa) // [[1], [3]]
  console.log(bbb) // [1, 3]