input: Write a python function to calculate the number of integer coordinates within a given square.
  assert count_integral_coordinates(1, 1, 4, 4) == 4
  assert count_integral_coordinates(1, 2, 1, 2) == 1
  assert count_integral_coordinates(4, 2, 6, 4) == 1
output: def count_integral_coordinates(x1, y1, x2, y2):
      min_x, max_x = min(x1, x2), max(x1, x2)
      min_y, max_y = min(y1, y2), max(y1, y2)
      count = 0
      for x in range(min_x, max_x + 1):
          for y in range(min_y, max_y + 1):
              count += 1
      return count