function groupByRange(numbers: number[], rangeSize: number): Record<string, number[]> {
  let output:Record<string, number[]> = {};

  for(let i = 0 ; i < numbers.length; i++){
    const num = numbers[i];
    const start = Math.floor(num/rangeSize) * rangeSize
    const key = `${start}-${start + rangeSize}`;

    if(!output[key]) output[key] = []
    output[key].push(num);
  }
  


  return output;
}

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