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import math
seat_ids = list()
with open("input", "r") as passes:
for seat in passes:
front = 0
back = 127
left = 0
right = 7
for i in seat:
if i == "F":
back = math.floor((front + back) / 2)
elif i == "B":
front = math.ceil((front + back) / 2)
elif i == "L":
right = math.floor((right + left) / 2)
else:
left = math.ceil((right + left) / 2)
assert front == back
assert left == right
row = front
col = left
seat_id = row * 8 + col
seat_ids.append(seat_id)
seat_ids.sort()
# answer to the first part
print(seat_ids[-1])
# answer to the second part
lent = len(seat_ids)
left = 0
right = lent - 1
cursor = 0
while right - left > 1:
cursor = math.ceil((left + right) / 2)
if (seat_ids[left] - left) != (seat_ids[cursor] - cursor):
right = cursor
elif (seat_ids[right] - right) != (seat_ids[cursor] - cursor):
left = cursor
print(seat_ids[cursor] + 1)
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