function groupByRange(numbers: number[], rangeSize: number): Record<string, number[]> {
  // Escribe tu solución aquí
  console.log(Math.floor(numbers[0] / rangeSize) * rangeSize)
 return numbers.reduce((acc, n) => {
    const start = Math.floor(n / rangeSize) * rangeSize;
    
    const key = `${start}-${start + rangeSize}`;

    (acc[key] ??= []).push(n);

    return acc;
  }, {} as Record<string, number[]>);
}

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