function countPaths(rows: number, cols: number): number {
  const matrix: number[][] = Array.from({ length: rows },
    () => Array.from({ length: cols },
      () => 0
    ))

  for (let i = 0; i < rows; i++) {
    for (let j = 0; j < cols; j++) {
      if (i === 0 || j === 0) {
        matrix[i][j] = 1
      } else {
        matrix[i][j] = matrix[i - 1][j] + matrix[i][j - 1]
      }
    }
  }

  return matrix[rows - 1][cols - 1];
}

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