text: """
  Problem 15: Lattice paths
  https://projecteuler.net/problem=15
  
  Starting in the top left corner of a 2x2 grid, and only being able to move to the right and down,
  there are exactly 6 routes to the bottom right corner.
  How many such routes are there through a 20×20 grid?
  """
  
  
  def test_loop_solution():
      # arrange
      from src.p015_lattice_paths import loop_solution
  
      # act
      actual_result = loop_solution(2)
  
      # assert
      assert actual_result == 6
  
  
  def test_closed_form_solution():
      # arrange
      from src.p015_lattice_paths import closed_form_solution
  
      # act
      actual_result = closed_form_solution(2)
  
      # assert
      assert actual_result == 6
  