Merge Intervals LeetCode solution in JavaScript

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/**
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 * @param {number[][]} intervals
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 * @return {number[][]}
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 */
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var merge = function (intervals) {
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  // sorting the intervals array first is a general good first step
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  intervals.sort((a, b) => a[0] - b[0]);
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  const result = [];
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  // i am using the result array as a way to compare previous and next intervals
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  result.push(intervals[0]);
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  for (let i = 1; i < intervals.length; i++) {
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    const prevInterval = result[result.length - 1];
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    const interval = intervals[i];
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    if (prevInterval[1] >= interval[0]) {
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      // overlap detected
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      const [l, r] = result.pop();
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      // if overlap, merge intervals by taking min/max of both boundaries
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      const newL = Math.min(l, interval[0]);
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      const newR = Math.max(r, interval[1]);
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      result.push([newL, newR]);
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    } else {
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      result.push(intervals[i]);
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    }
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  }
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  return result;
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};