从递归中得到总数

Question

我有一个对象数组，它引用了它的集合const data = [{    id: 1,    name: 'A',    referer_id: null,    point: 4  },  {    id: 2,    name: 'B',    referer_id: 1,    point: 100  },  {    id: 3,    name: 'C',    referer_id: null,    point: 4  },  {    id: 4,    name: 'D',    referer_id: 1,    point: 2  },  {    id: 5,    name: 'E',    referer_id: null,    point: 4  },  {    id: 6,    name: 'F',    referer_id: null,    point: 4  },  {    id: 7,    name: 'G',    referer_id: 2,    point: 4  },];referer id 将引用该 id。我还有另一个数字数组用于计算点const pointsByLevel = [0.5, 0.3, 0.2]; // this would be dynamic from database截至目前，我可以像这样得到所有总数的总和function getPoint(user_id) {  const mainUserPoint = data.find((u) => u.id === user_id).point;  let sum = 0;    for (let subdep of data.filter((d) => d.referer_id === user_id)) {    sum += getPoint(subdep.id);  }  return mainUserPoint + sum;}但真正的挑战是第一级应该只返回点数，但之后点数将根据pointsByLevel索引乘以所以输出会是这样的console.log(getPoint(1));/**A - 4B D - [100 * 0.5], [2 * 0.5]G - [4 * 0.3]**/// 4 + 50 + 1 + 1.2 = 56.2所以最终结果我会得到 56.2最有效的方法是什么

Answer 1

作为 的附加参数，您必须跟踪您的深度级别getPoint。将默认值设置为 0，并在每次递归时递增它。然后你可以为它逐级找到对应的点。（我为 0 级插入了 1.0 系数）。我还添加了评论以显示每个级别的部分结果。

const data = [

  { id: 1, name: 'A', referer_id: null, point: 4 },

  { id: 2, name: 'B', referer_id: 1, point: 100 },

  { id: 3, name: 'C', referer_id: null, point: 4 },

  { id: 4, name: 'D', referer_id: 1, point: 2 },

  { id: 5, name: 'E', referer_id: null, point: 4 },

  { id: 6, name: 'F', referer_id: null, point: 4 },

  { id: 7, name: 'G', referer_id: 2, point: 4 }

];

const pointsByLevel = [1, 0.5, 0.3, 0.2]; //  NOTE: I added a 1.0 for level 0

function getPoint(user_id, level = 0) {

  const user = data.find((u) => u.id === user_id);

  const mainUserPoint = user.point;

  let sum = 0;

  for (let subdep of data.filter((d) => d.referer_id === user_id)) {

    let val = getPoint(subdep.id, level + 1);

    sum += val;

  }

  let result = (mainUserPoint * pointsByLevel[level]) + sum;

  console.log(`getPoint for ${user_id} "${user.name}" is ${level} levels deep and has the value ${result}`)

  return result;

}

console.log(getPoint(1));