output_description: Print the maximum possible radius of the circles. The absolute error or the
  relative error must be at most 10^{-9}.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      x_1 y_1
      x_2 y_2
      x_3 y_3
attempt: import math
  
  xy = []
  for i in range(3):
      xy.append([int(item) for item in input().split()])
  xy.append(xy[0])
  
  dist = []
  for i in range(3):
      distance = math.sqrt(
          (xy[i][0] - xy[i + 1][0]) ** 2.0 + (xy[i][1] - xy[i + 1][1]) ** 2.0
      )
      dist.append([distance, i, (i + 1) % 3, (i + 2) % 3])
  dist.sort(reverse=True)
  
  
  def get_vector(a, b):
      v = [a[0] - b[0], a[1] - b[1]]
      return v
  
  
  def norm(a):
      n = math.sqrt(a[0] * a[0] + a[1] * a[1])
      return n
  
  
  a = get_vector(xy[dist[0][-1]], xy[dist[0][-2]])
  b = get_vector(xy[dist[0][-3]], xy[dist[0][-2]])
  c = get_vector(xy[dist[0][-1]], xy[dist[0][-3]])
  d = get_vector(xy[dist[0][-2]], xy[dist[0][-3]])
  bc = dist[0][0]
  
  ctheta = (a[0] * b[0] + a[1] * b[1]) / (norm(a) * norm(b))
  cphi = (c[0] * d[0] + c[1] * d[1]) / (norm(c) * norm(d))
  htheta = (math.pi - math.acos(ctheta)) / 2.0
  hphi = (math.pi - math.acos(ctheta)) / 2.0
  r = bc / (math.tan(htheta) + math.tan(hphi) + 2)
  print(r)
  
problem_description: Statement
  
  Snuke received a triangle as a birthday present. The coordinates of the three
  vertices were (x_1, y_1), (x_2, y_2), and (x_3, y_3).
  
  He wants to draw two circles with the same radius inside the triangle such
  that the two circles do not overlap (but they may touch). Compute the maximum
  possible radius of the circles.
samples: [{"input": "0 0\n    1 1\n    2 0", "output": "0.292893218813\n    \n\n* * *"}, {"input": "3 1\n    1 5\n    4 9", "output": "0.889055514217"}]