55 lines
1.2 KiB
Python
55 lines
1.2 KiB
Python
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def read_file():
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with open("input.txt","r") as f:
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return f.read().split('\n')
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def find_row(rowpart):
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row = [*range(128)] # create a list using unpack operator
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for c in rowpart:
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if c == 'F':
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row = row[:len(row)//2] # lower half
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elif c == 'B':
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row = row[len(row)//2:] # upper half
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else:
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break
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return row[0] # extract from list
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def find_col(colpart):
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col = [*range(8)] # create a list using unpack operator
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for c in colpart:
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if c == 'L':
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col = col[:len(col)//2] # lower half
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elif c == 'R':
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col = col[len(col)//2:] # upper half
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else:
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break
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return col[0] # extract from list
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def id(seat):
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rowpart = seat[:-3]
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colpart = seat[7:]
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row = find_row(rowpart)
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col = find_col(colpart)
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return 8*row + col
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def part1(seats):
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max_id = 0
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for seat in seats:
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if id(seat) > max_id:
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max_id = id(seat)
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return max_id
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def part2(seats):
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ids = sorted(map(id, seats))
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prev_id = 0
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for seat_id in ids:
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if seat_id - prev_id == 2: # gap detected
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return seat_id - 1 # so your seat is the one right before
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prev_id = seat_id
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def main():
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seats = read_file()
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print(f'{part1(seats)=}')
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print(f'{part2(seats)=}')
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if __name__ == "__main__":
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main()
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