Bagaimanakah saya boleh menambah baik logik bersarang ini untuk menjadikannya berfungsi dengan betul dan meningkatkan prestasi

Editor PHP Yuzai, anda mungkin menghadapi masalah dengan logik bersarang semasa menulis kod, menyebabkan kod tidak berfungsi dengan baik atau mempunyai prestasi rendah. Untuk memperbaiki masalah ini, terdapat beberapa perkara penting yang perlu dipertimbangkan. Mula-mula, anda boleh menyemak semula struktur logik anda untuk melihat sama ada anda boleh memudahkan atau menyusun semula kod anda untuk mengurangkan tahap bersarang. Kedua, anda boleh mempertimbangkan untuk menggunakan struktur data dan algoritma yang sesuai untuk mengoptimumkan kod anda. Selain itu, pastikan kod anda tidak menduplikasi pengiraan atau operasi berlebihan untuk meningkatkan prestasi. Akhir sekali, lakukan ujian dan penyahpepijatan yang sesuai untuk memastikan kod anda berfungsi dengan baik dalam pelbagai keadaan. Melalui kaedah ini, anda boleh meningkatkan logik bersarang dan meningkatkan prestasi kod anda.

Kandungan soalan

Saya mempunyai pangkalan data yang mengandungi ulasan, setiap ulasan mempunyai ID dan ID ibu bapa. Matlamatnya hanyalah untuk meletakkan setiap ulasan dengan ID induk di bawah ulasan induknya dengan cara yang cekap.

Saya pada mulanya menggunakan fungsi rekursif untuk mencari anotasi induk dalam tatasusunan arranged, tetapi prestasinya sangat teruk. Saya memfaktorkan semula untuk menggunakan penunjuk untuk menjejaki induk, yang berfungsi hampir sempurna, tetapi nampaknya komen terakhir yang akan diproses sentiasa dikecualikan daripada output.

Dalam contoh di bawah, "ulasan 1" sepatutnya merupakan anak kepada "ulasan 11", tetapi ia tidak termasuk dalam output sama sekali.

package main

import (
  "encoding/json"
  "fmt"
)

// Comment from Database
type Comment struct {
  ID       string `json:"id""`
  ParentID string `json:"pid"`
  Text     string `json:"text"`
}

// NestedComment output
type NestedComment struct {
  Comment
  Children []NestedComment `json:"children,omitempty"`
}

func main() {
  // Some comment data from DB
  jsondata := `[{"id":"f1c3a838-f4b4-4ebd-bb1b-d3e4c0dce27d","pid":"6a162b3f-9341-46e9-95f7-dedc6cd06868","text":"comment 1"},{"id":"131cf4bb-1971-43a2-992f-2cbb042a4184","pid":"","text":"comment 2"},{"id":"4c93a789-ecab-4173-954c-b039cd3a9e17","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 3"},{"id":"c7974b6d-67e1-47d0-84fa-c78d51682df2","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 4"},{"id":"386c4439-4596-47c1-99bf-cb479055fe5a","pid":"","text":"comment 5"},{"id":"5ef0816e-ea13-4a7e-8009-e67ee08ef906","pid":"386c4439-4596-47c1-99bf-cb479055fe5a","text":"comment 6"},{"id":"96b0a536-602b-4f3f-a352-020f22cdfb18","pid":"","text":"comment 7"},{"id":"d0f11e98-deea-4fd5-becb-8f406ebcae83","pid":"96b0a536-602b-4f3f-a352-020f22cdfb18","text":"comment 8"},{"id":"bad87461-3cbf-4ecb-a8c7-36876b57d652","pid":"","text":"comment 9"},{"id":"e3ee6f90-495f-4348-9c29-bd6e15ec3b39","pid":"bad87461-3cbf-4ecb-a8c7-36876b57d652","text":"comment 10"},{"id":"6a162b3f-9341-46e9-95f7-dedc6cd06868","pid":"","text":"comment 11"},{"id":"041c7c2d-0688-491e-b6cd-899eac95bd3d","pid":"","text":"comment 12"},{"id":"5acdf3ff-345b-47a5-bd66-a6687a1441b7","pid":"041c7c2d-0688-491e-b6cd-899eac95bd3d","text":"comment 13"},{"id":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","pid":"","text":"comment 14"},{"id":"6108b28c-a7af-4c5a-a38c-c22db0d34b31","pid":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","text":"comment 15"},{"id":"1736393e-95b0-4f5d-a149-50fe52c28350","pid":"","text":"comment 16"},{"id":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","pid":"1736393e-95b0-4f5d-a149-50fe52c28350","text":"comment 17"},{"id":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","pid":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","text":"comment 18"},{"id":"76e49597-6039-4cb5-a595-556ccc2e3c12","pid":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","text":"comment 19"},{"id":"07dc4b90-65d3-4f75-8351-457305988235","pid":"76e49597-6039-4cb5-a595-556ccc2e3c12","text":"comment 20"},{"id":"2d4e838b-82df-4ca0-bf9b-f1dfb99d6763","pid":"07dc4b90-65d3-4f75-8351-457305988235","text":"comment 21"},{"id":"617c1760-0dca-409c-af2a-c614f0530e07","pid":"","text":"comment 22"},{"id":"712c0b7e-a9e4-40fd-ab78-c39b483b1435","pid":"617c1760-0dca-409c-af2a-c614f0530e07","text":"comment 23"},{"id":"e325094c-886e-42c9-bd59-fdd7a189b384","pid":"","text":"comment 24"},{"id":"f3b8b0f9-edef-4ee6-9555-42e8595f854c","pid":"e325094c-886e-42c9-bd59-fdd7a189b384","text":"comment 25"},{"id":"6e09a231-a2ee-4aa1-a898-57695e6fe153","pid":"","text":"comment 26"},{"id":"63e629d6-c0f9-4b36-ad96-e0c47cf8bb4e","pid":"6e09a231-a2ee-4aa1-a898-57695e6fe153","text":"comment 27"},{"id":"d7b698f1-8757-46db-a6e6-5141a481b42b","pid":"","text":"comment 28"},{"id":"a7e3d522-553c-44f1-befa-047bd94f0e59","pid":"","text":"comment 29"},{"id":"fe78ce24-c2c8-4d00-b96d-8b8be9ce0f06","pid":"","text":"comment 30"},{"id":"fabdccb5-a024-4476-bd51-7d55fb685c42","pid":"","text":"comment 31"},{"id":"608d0693-6e43-46a0-9e54-107da6adb109","pid":"fabdccb5-a024-4476-bd51-7d55fb685c42","text":"comment 32"}]`

  var comments []Comment

  err := json.Unmarshal([]byte(jsondata), &comments)
  if err != nil {
    panic(err)
  }

  arranged := ArrangeComments(comments, len(comments))

  arrangedjson, _ := json.MarshalIndent(arranged, "", "  ")

  fmt.Println(string(arrangedjson))
  fmt.Println("comments", len(comments), "arranged", recursiveCount(arranged))
}

func recursiveCount(arranged []NestedComment) int {
    count := len(arranged)
    for _, item := range arranged {
        count += recursiveCount(item.Children)
    }
    return count
}

// Nesting function -------------------------------------------------------------------------

func ArrangeComments(queue []Comment, count int) []NestedComment {
  var arranged []NestedComment

  // using pointers over a recursive search
  var refs []*NestedComment

  // some comments are orphaned, se we need a bail out
  tries := 0
  maxTries := 5
  prevPlacedLen := 0

  // IDs of placed comments
  var placed []string

  // while count is greater then length of placed
countloop:
  for count > len(placed) {
    // loop through queue
  queueloop:
    for _, item := range queue {

      // skip if already placed
      if len(placed) > 0 {
        for _, id := range placed {
          if id == item.ID {
            continue queueloop
          }
        }
      }

      // if parent is nil, add to arranged
      if item.ParentID == "" {
        arranged = append(arranged, NestedComment{
          Comment: item,
        })
        refs = append(refs, &arranged[len(arranged)-1])
        placed = append(placed, item.ID)
      } else {
        // if parent is not nil, loop through refs and add to children
      refloop:
        for _, ref := range refs {
          if ref.ID == item.ParentID {
            ref.Children = append(ref.Children, NestedComment{Comment: item})
            refs = append(refs, &ref.Children[len(ref.Children)-1])
            placed = append(placed, item.ID)
            break refloop
          }
        }
      }
    }

    // if no comments were placed, bail out after x tries
    if len(placed) == prevPlacedLen {
      if tries >= maxTries {
        break countloop
      }
      tries++
      break
    }

    prevPlacedLen = len(placed)
  }

  return arranged
}

Kemas kini; ini membuatkan saya lebih dekat, tetapi tidak dapat menyusun beberapa komen bersarang yang lebih mendalam. Peliknya, ia menghasilkan output yang berbeza setiap kali ia dijalankan:

func ArrangeComments(comments []Comment) []NestedComment {
    // Map to hold references to NestedComment by their ID
    queue := make(map[string]*NestedComment)

    // Result slice
    var result []NestedComment

    // First, create all NestedComments and store references in the map
    for _, comment := range comments {
        nc := &NestedComment{Comment: comment}
        queue[comment.ID] = nc
    }

    // Second, loop through the map and add children to their parents
    for _, comment := range queue {
        if comment.ParentID != "" {
            parent := queue[comment.Comment.ParentID]
            if parent != nil {
                parent.Children = append(parent.Children, *comment)
            }
        }
    }

    // Third, loop through the map and add all root comments to the result slice
    for _, comment := range queue {
        if comment.ParentID == "" {
            result = append(result, *comment)
        }
    }

    return result
}

Kemas kini; Saya dengan cepat menulis pelaksanaan JavaScript yang menghasilkan hasil yang betul dengan data sampel yang sama, tetapi saya tidak dapat mengetahui sebab kod JS ini berfungsi dan kod Go tidak.

const datajson = `[{"id":"f1c3a838-f4b4-4ebd-bb1b-d3e4c0dce27d","pid":"6a162b3f-9341-46e9-95f7-dedc6cd06868","text":"comment 1"},{"id":"131cf4bb-1971-43a2-992f-2cbb042a4184","pid":"","text":"comment 2"},{"id":"4c93a789-ecab-4173-954c-b039cd3a9e17","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 3"},{"id":"c7974b6d-67e1-47d0-84fa-c78d51682df2","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 4"},{"id":"386c4439-4596-47c1-99bf-cb479055fe5a","pid":"","text":"comment 5"},{"id":"5ef0816e-ea13-4a7e-8009-e67ee08ef906","pid":"386c4439-4596-47c1-99bf-cb479055fe5a","text":"comment 6"},{"id":"96b0a536-602b-4f3f-a352-020f22cdfb18","pid":"","text":"comment 7"},{"id":"d0f11e98-deea-4fd5-becb-8f406ebcae83","pid":"96b0a536-602b-4f3f-a352-020f22cdfb18","text":"comment 8"},{"id":"bad87461-3cbf-4ecb-a8c7-36876b57d652","pid":"","text":"comment 9"},{"id":"e3ee6f90-495f-4348-9c29-bd6e15ec3b39","pid":"bad87461-3cbf-4ecb-a8c7-36876b57d652","text":"comment 10"},{"id":"6a162b3f-9341-46e9-95f7-dedc6cd06868","pid":"","text":"comment 11"},{"id":"041c7c2d-0688-491e-b6cd-899eac95bd3d","pid":"","text":"comment 12"},{"id":"5acdf3ff-345b-47a5-bd66-a6687a1441b7","pid":"041c7c2d-0688-491e-b6cd-899eac95bd3d","text":"comment 13"},{"id":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","pid":"","text":"comment 14"},{"id":"6108b28c-a7af-4c5a-a38c-c22db0d34b31","pid":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","text":"comment 15"},{"id":"1736393e-95b0-4f5d-a149-50fe52c28350","pid":"","text":"comment 16"},{"id":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","pid":"1736393e-95b0-4f5d-a149-50fe52c28350","text":"comment 17"},{"id":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","pid":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","text":"comment 18"},{"id":"76e49597-6039-4cb5-a595-556ccc2e3c12","pid":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","text":"comment 19"},{"id":"07dc4b90-65d3-4f75-8351-457305988235","pid":"76e49597-6039-4cb5-a595-556ccc2e3c12","text":"comment 20"},{"id":"2d4e838b-82df-4ca0-bf9b-f1dfb99d6763","pid":"07dc4b90-65d3-4f75-8351-457305988235","text":"comment 21"},{"id":"617c1760-0dca-409c-af2a-c614f0530e07","pid":"","text":"comment 22"},{"id":"712c0b7e-a9e4-40fd-ab78-c39b483b1435","pid":"617c1760-0dca-409c-af2a-c614f0530e07","text":"comment 23"},{"id":"e325094c-886e-42c9-bd59-fdd7a189b384","pid":"","text":"comment 24"},{"id":"f3b8b0f9-edef-4ee6-9555-42e8595f854c","pid":"e325094c-886e-42c9-bd59-fdd7a189b384","text":"comment 25"},{"id":"6e09a231-a2ee-4aa1-a898-57695e6fe153","pid":"","text":"comment 26"},{"id":"63e629d6-c0f9-4b36-ad96-e0c47cf8bb4e","pid":"6e09a231-a2ee-4aa1-a898-57695e6fe153","text":"comment 27"},{"id":"d7b698f1-8757-46db-a6e6-5141a481b42b","pid":"","text":"comment 28"},{"id":"a7e3d522-553c-44f1-befa-047bd94f0e59","pid":"","text":"comment 29"},{"id":"fe78ce24-c2c8-4d00-b96d-8b8be9ce0f06","pid":"","text":"comment 30"},{"id":"fabdccb5-a024-4476-bd51-7d55fb685c42","pid":"","text":"comment 31"},{"id":"608d0693-6e43-46a0-9e54-107da6adb109","pid":"fabdccb5-a024-4476-bd51-7d55fb685c42","text":"comment 32"}]`

const queue = JSON.parse(datajson)

const result = []

const queueMap = new Map(queue.map(item => [item.id, item]))

for (const item of queue) {
  if (item.pid !== '') {
    const parent = queueMap.get(item.pid)
    if (parent) {
      if (!parent.children) {
        parent.children = []
      }
      parent.children.push(item)
    }
  }
}

for (const [_, value] of queueMap) {
  if (value.pid === '') {
    result.push(value)
  }
}

function recursiveCount(res) {
  let count = res.length
  res.forEach(item => {
    if (item.children) {
      count += recursiveCount(item.children)
    }
  });
  return count
}


console.log(JSON.stringify(result, null, 2))
console.log("comments", queue.length, "arranged", recursiveCount(result))

Contoh Runnable Go: https://gist.github.com/dlford/9e66069cfc7fb9afc649c5e3dc650083

Contoh JS boleh dijalankan: https://gist.github.com/dlford/f6f4a383a99f65659895ed51d1a4b651

Go output kod (lihat kiraan di bawah): https://gist.github.com/dlford/302c4db939c21d15132848368caa01ec

Output kod JS (lihat kiraan di bawah): https://gist.github.com/dlford/60ab49d0466c957c7745059022e27e09

Penyelesaian

Masalahnya ialah NestedComment 中的 Children juga perlu disimpan sebagai penunjuk.

Contoh kerja:

package main

import (
    "encoding/json"
    "fmt"
)

// Comment from Database
type Comment struct {
    ID       string `json:"id"`
    ParentID string `json:"pid"`
    Text     string `json:"text"`
}

// NestedComment output
type NestedComment struct {
    Comment
    Children []*NestedComment `json:"children,omitempty"`
}

func main() {
    // Some comment data from DB
    jsondata := `[{"id":"f1c3a838-f4b4-4ebd-bb1b-d3e4c0dce27d","pid":"6a162b3f-9341-46e9-95f7-dedc6cd06868","text":"comment 1"},{"id":"131cf4bb-1971-43a2-992f-2cbb042a4184","pid":"","text":"comment 2"},{"id":"4c93a789-ecab-4173-954c-b039cd3a9e17","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 3"},{"id":"c7974b6d-67e1-47d0-84fa-c78d51682df2","pid":"131cf4bb-1971-43a2-992f-2cbb042a4184","text":"comment 4"},{"id":"386c4439-4596-47c1-99bf-cb479055fe5a","pid":"","text":"comment 5"},{"id":"5ef0816e-ea13-4a7e-8009-e67ee08ef906","pid":"386c4439-4596-47c1-99bf-cb479055fe5a","text":"comment 6"},{"id":"96b0a536-602b-4f3f-a352-020f22cdfb18","pid":"","text":"comment 7"},{"id":"d0f11e98-deea-4fd5-becb-8f406ebcae83","pid":"96b0a536-602b-4f3f-a352-020f22cdfb18","text":"comment 8"},{"id":"bad87461-3cbf-4ecb-a8c7-36876b57d652","pid":"","text":"comment 9"},{"id":"e3ee6f90-495f-4348-9c29-bd6e15ec3b39","pid":"bad87461-3cbf-4ecb-a8c7-36876b57d652","text":"comment 10"},{"id":"6a162b3f-9341-46e9-95f7-dedc6cd06868","pid":"","text":"comment 11"},{"id":"041c7c2d-0688-491e-b6cd-899eac95bd3d","pid":"","text":"comment 12"},{"id":"5acdf3ff-345b-47a5-bd66-a6687a1441b7","pid":"041c7c2d-0688-491e-b6cd-899eac95bd3d","text":"comment 13"},{"id":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","pid":"","text":"comment 14"},{"id":"6108b28c-a7af-4c5a-a38c-c22db0d34b31","pid":"aaee2ae5-7e3a-4435-a094-83bf6b77abfb","text":"comment 15"},{"id":"1736393e-95b0-4f5d-a149-50fe52c28350","pid":"","text":"comment 16"},{"id":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","pid":"1736393e-95b0-4f5d-a149-50fe52c28350","text":"comment 17"},{"id":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","pid":"b646f202-17aa-4af9-b8dc-c1d8ff3529ac","text":"comment 18"},{"id":"76e49597-6039-4cb5-a595-556ccc2e3c12","pid":"a8827b1d-fdbc-41c2-bdb5-38e8b308dedc","text":"comment 19"},{"id":"07dc4b90-65d3-4f75-8351-457305988235","pid":"76e49597-6039-4cb5-a595-556ccc2e3c12","text":"comment 20"},{"id":"2d4e838b-82df-4ca0-bf9b-f1dfb99d6763","pid":"07dc4b90-65d3-4f75-8351-457305988235","text":"comment 21"},{"id":"617c1760-0dca-409c-af2a-c614f0530e07","pid":"","text":"comment 22"},{"id":"712c0b7e-a9e4-40fd-ab78-c39b483b1435","pid":"617c1760-0dca-409c-af2a-c614f0530e07","text":"comment 23"},{"id":"e325094c-886e-42c9-bd59-fdd7a189b384","pid":"","text":"comment 24"},{"id":"f3b8b0f9-edef-4ee6-9555-42e8595f854c","pid":"e325094c-886e-42c9-bd59-fdd7a189b384","text":"comment 25"},{"id":"6e09a231-a2ee-4aa1-a898-57695e6fe153","pid":"","text":"comment 26"},{"id":"63e629d6-c0f9-4b36-ad96-e0c47cf8bb4e","pid":"6e09a231-a2ee-4aa1-a898-57695e6fe153","text":"comment 27"},{"id":"d7b698f1-8757-46db-a6e6-5141a481b42b","pid":"","text":"comment 28"},{"id":"a7e3d522-553c-44f1-befa-047bd94f0e59","pid":"","text":"comment 29"},{"id":"fe78ce24-c2c8-4d00-b96d-8b8be9ce0f06","pid":"","text":"comment 30"},{"id":"fabdccb5-a024-4476-bd51-7d55fb685c42","pid":"","text":"comment 31"},{"id":"608d0693-6e43-46a0-9e54-107da6adb109","pid":"fabdccb5-a024-4476-bd51-7d55fb685c42","text":"comment 32"}]`

    var comments []Comment

    err := json.Unmarshal([]byte(jsondata), &comments)
    if err != nil {
        panic(err)
    }

    arranged := ArrangeComments(comments)

    arrangedjson, _ := json.MarshalIndent(arranged, "", "  ")

    fmt.Println(string(arrangedjson))
    fmt.Println("comments", len(comments), "arranged", recursiveCount(arranged))
}

func recursiveCount(arranged []*NestedComment) int {
    count := len(arranged)
    for _, item := range arranged {
        count += recursiveCount(item.Children)
    }
    return count
}

// Nesting function -------------------------------------------------------------------------

func ArrangeComments(comments []Comment) []*NestedComment {
    // Map to hold references to NestedComment by their ID
    queue := make(map[string]*NestedComment)

    // Result slice
    var result []*NestedComment

    // First, create all NestedComments and store references in the map
    for _, comment := range comments {
        nc := &NestedComment{Comment: comment}
        queue[comment.ID] = nc
    }

    // Second, loop through the map and add children to their parents
    for _, comment := range queue {
        if comment.ParentID != "" {
            parent := queue[comment.Comment.ParentID]
            if parent != nil {
                parent.Children = append(parent.Children, comment)
            }
        }
    }

    // Third, loop through the map and add all root comments to the result slice
    for _, comment := range queue {
        if comment.ParentID == "" {
            result = append(result, comment)
        }
    }

    return result
}

Atas ialah kandungan terperinci Bagaimanakah saya boleh menambah baik logik bersarang ini untuk menjadikannya berfungsi dengan betul dan meningkatkan prestasi. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!