draw H tree - code review - mock interview

DrawHTree_codereview.ps

# center = (x,y)
# first line will be;  left_point (x - length/2, y) -------------  (x + length/2, y) right_point
#
#                          *   * 
#                          *****
#                          *   * 
# point (a,b) ==> (a, b - length/2) ..... (a, b + length/2)

# drawHTree(length, x, y, depth):
#      left_point, right_point
#      drawline(left_point, right_point)

#      upper_left, lower_left
#      drawline(upper_left, lower_left)

#      upper_right, lower_right
#      drawline(upper_right, lower_right)
#      
#      depth -=1
#      if depth >=0:
#          for center in (upper_left, lower_left, upper_right, lower_right )
#             drawHTree(length/sqrt(2), *center, depth): 

# space complexity O(1)
# time complexity
# 0th: 3
# 1th: 4*3
# 2th: 4*4*3
# ...  (pow(4,0) + ... + pow(4, depth))*3

# O(power(4,depth))

def drawLine(point1, point2):
  # point = (x,y)
  print(point1,"----",point2)
 
def drawHTree(length, center, depth):
  
  if depth == 0:
    return
  
  half = length/ 2
  
  left_point  = (center[0] - half, center[1]) 
  right_point = (center[0] + half, center[1]) 
  
  upper_left = (left_point[0], left_point[1]  - half)  
  lower_left = (left_point[0], left_point[1]  + half)   
  
  upper_right = (right_point[0], right_point[1] - half)
  lower_right = (right_point[0], right_point[1] + half)
  
  drawLine(left_point,  right_point)
  drawLine(upper_left,  lower_left)
  drawLine(upper_right, lower_right)
  
  depth -= 1

  length /= pow(2, 0.5)
  for center in [upper_left, lower_left, upper_right, lower_right]:
    drawHTree(length, center, depth)
      
  
drawHTree(10, (0,0), 2)