Dynamic programming-polygon game

Posted 2020-07-07

polygon_vertex=[5,-7,4,2]
polygon_side=[‘+‘,‘+‘,‘*‘,‘*‘]

multi_list = [[[0 for col in range(5)] for row in range(5)] for i in range(5)]

def get_min_of_four(val_1, val_2, val_3, val_4):
 minium = val_1
 if minium> val_2:
  minium = val_2
 if minium > val_3:
  minium = val_3
 if minium > val_4:
     minium = val_4
 return minium

def get_max_of_four(val_1, val_2, val_3, val_4):
 maximum = val_1
 if maximum < val_2:
  maximum = val_2
 if maximum < val_3:
  maximum = val_3
 if maximum < val_4:
     maximum = val_4
 return maximum

def get_min_and_max(multi_list, vertex, split, length):
 first_seg_min = multi_list[vertex][split][0]
 first_seg_max = multi_list[vertex][split][1]
 second_seg_vertex = (vertex+split)%4
 second_seg_min = multi_list[second_seg_vertex][length-split][0]
 second_seg_max = multi_list[second_seg_vertex][length-split][1]
 index = (vertex+split-1)%4
 oper = polygon_side[index]
 if oper == ‘+‘:
  return first_seg_min+ second_seg_min, first_seg_max + second_seg_max
 else:
  val_1 = first_seg_min * second_seg_min
  val_2 = first_seg_min * second_seg_max
  val_3 = first_seg_max * second_seg_min
  val_4 = first_seg_max * second_seg_max
  return get_min_of_four(val_1, val_2, val_3, val_4), get_max_of_four(val_1, val_2, val_3, val_4)

def calc_max_val(multi_list):
 for i in range(0,4):
  multi_list[i][1][0] = polygon_vertex[i]
  multi_list[i][1][1] = polygon_vertex[i]
 for length in range(2,5):
  for vertex in range(0,4):
   minimum, maximum = get_min_and_max(multi_list, vertex, 1, length)
   for split in range(2,length):
    cur_minimum, cur_maximum = get_min_and_max(multi_list, vertex, split, length)
    if cur_minimum < minimum:
     minimum = cur_minimum
    if cur_maximum > maximum:
     maximum = cur_maximum
   multi_list[vertex][length][0] = minimum
   multi_list[vertex][length][1] = maximum
   print vertex, minimum, maximum, length

 

calc_max_val(multi_list)

def get_maximum(multi_list):
 max_index=0
 maximum = multi_list[0][4][1]
 for i in range(0,4):
  # maximum = multi_list[i][4][1]
  print i, multi_list[i][4][1]
  if multi_list[i][4][1] > maximum:
   maximum = multi_list[i][4][1]
   max_index = i
 return maximum, max_index

print get_maximum(multi_list)