function mergeIntervals(intervals: [number, number][]): [number, number][] {
  intervals.sort((a,b) => a[0] - b[0])
  let merged = []

  for (const interval of intervals) {
    if (merged.length === 0 || interval[0] > merged[merged.length - 1][1]) {
      merged.push(interval)
    } else {
      merged[merged.length - 1][1] = Math.max(merged[merged.length - 1][1], interval[1])
    }
  }

  return merged;
}

// No modificar: necesario para evaluar el resultado.
export { mergeIntervals };