43 lines
1.2 KiB
Python
43 lines
1.2 KiB
Python
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from math import floor,ceil
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input_file = "input.txt"
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seats = []
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with open(input_file) as boardings:
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line = boardings.readline()
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while line and line != "\n":
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row_start = 0
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row_end = 127
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column_start = 0
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column_end = 7
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for character in line:
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if character == "F":
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row_end = floor((row_start+row_end)/2)
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elif character == "B":
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row_start = ceil((row_start+row_end)/2)
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elif character == "L":
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column_end = floor((column_start+column_end)/2)
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elif character == "R":
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column_start = ceil((column_start+column_end)/2)
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else: # End of line
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seats.append(row_end*8+column_end)
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line = boardings.readline()
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print(f"Highest seat ID : {max(seats)}")
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seats.sort()
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possible_seats = list(range(seats[0], seats[-1]+1))
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# There might be missing seats at the front or the back of the plane
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# thus, if we sort and create a range between the smallest and largest ID
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# and iterate over both, the number missing in the full range would be our seat.
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for i in range(len(seats)):
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if seats[i] != possible_seats[i]:
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print(f"Your seat is {possible_seats[i]}")
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break
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