function buildStaircase(n: number): number[][] {

  const output = [];
  let lastNumber = 0

  for( let i = 1; i<= n; i++) {

    const arrayElements =  Array.from({ length: i}, (_, idx) => idx + lastNumber + 1);

    lastNumber = arrayElements.at(-1);

    output.push(arrayElements)
  }



  return output;
}

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