day5/get_seat_id.py

   1 #!/usr/bin/python3
   2
   3 def get_row(binary_id):
   4     choices=binary_id[:7]
   5
   6     selections=[a for a in range(128)]
   7
   8     for decision in choices:
   9         half_range=int(len(selections)/2)
  10         if decision == 'F':
  11             del selections[-half_range:]
  12         elif decision == 'B':
  13             del selections[:half_range]
  14
  15     return selections[0]
  16
  17 def get_col(binary_id):
  18     choices=binary_id[-3:]
  19
  20     selections=[a for a in range(8)]
  21
  22     for decision in choices:
  23         half_range=int(len(selections)/2)
  24         if decision == 'L':
  25             del selections[-half_range:]
  26         elif decision == 'R':
  27             del selections[:half_range]
  28
  29     return selections[0]
  30
  31 def get_seat(binary_id):
  32     row=get_row(binary_id)
  33     col=get_col(binary_id)
  34
  35     return ((row,col))
  36
  37 def get_seat_id(row, col):
  38     return ((row * 8) + col)
  39
  40 all_seat_ids=[]
  41
  42 for line in open("input.txt", "r"):
  43     line = line.rstrip()
  44
  45     (row, col) = get_seat(line)
  46     all_seat_ids.append(get_seat_id(row, col))
  47
  48 # sort the list
  49 all_seat_ids.sort()
  50
  51 # and print the highest seat id - part 1
  52 print("Highest seat id: {}".format(all_seat_ids[-1]))
  53
  54
  55 # part 2
  56 my_seat_id=None
  57
  58 for a,b in enumerate(all_seat_ids, start=all_seat_ids[0]):
  59     if a != b:
  60         my_seat_id=a
  61         break
  62
  63 print("My seat id: {}".format(my_seat_id))