K Closest Points to Origin LeetCode solution in JavaScript

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/**
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 * @param {number[][]} points
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 * @param {number} k
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 * @return {number[][]}
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 */
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var kClosest = function (points, k) {
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  let res = [];
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  let hashMap = new Map();
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  for (let i = 0; i < points.length; i++) {
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    //store the distance and the index of the points in a map
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    const dis = calcDis(points[i]);
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    hashMap.set(i, dis);
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  }
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  //sort the map by its distance to the origin
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  const hashMapNew = new Map([...hashMap].sort((a, b) => a[1] - b[1]));
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  //use the index sorted by distance to get the result
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  let i = 0;
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  for (const x of hashMapNew.keys()) {
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    //do it k times
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    if (i === k) break;
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    res.push(points[x]);
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    i++;
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  }
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  return res;
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};
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var calcDis = (b) => {
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  return Math.sqrt(Math.pow(b[0], 2) + Math.pow(b[1], 2));
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};