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+--- Day 5: Binary Boarding ---
+
+You board your plane only to discover a new problem: you dropped your boarding pass! You aren't sure
+which seat is yours, and all of the flight attendants are busy with the flood of people that
+suddenly made it through passport control.
+
+You write a quick program to use your phone's camera to scan all of the nearby boarding passes (your
+puzzle input); perhaps you can find your seat through process of elimination.
+
+Instead of zones or groups, this airline uses binary space partitioning to seat people.
+A seat might be specified like FBFBBFFRLR, where F means "front", B means "back", L means "left",
+and R means "right".
+
+The first 7 characters will either be F or B; these specify exactly one of the 128 rows
+on the plane (numbered 0 through 127). Each letter tells you which half of a region the given seat
+is in. Start with the whole list of rows; the first letter indicates whether the seat is in the
+front (0 through 63) or the back (64 through 127). The next letter
+indicates which half of that region the seat is in, and so on until you're left with exactly one
+row.
+
+For example, consider just the first seven characters of FBFBBFFRLR:
+
+- Start by considering the whole range, rows 0 through 127. - F means to take the lower
+half, keeping rows 0 through 63. - B means to take the upper half, keeping rows 32
+through 63. - F means to take the lower half, keeping rows 32 through 47. - B means to
+take the upper half, keeping rows 40 through 47. - B keeps rows 44 through 47. - F
+keeps rows 44 through 45. - The final F keeps the lower of the two, row 44.
+
+The last three characters will be either L or R; these specify exactly one of the 8
+columns of seats on the plane (numbered 0 through 7). The same process as above proceeds again,
+this time with only three steps. L means to keep the lower half, while R means to keep
+the upper half.
+
+For example, consider just the last 3 characters of FBFBBFFRLR:
+
+- Start by considering the whole range, columns 0 through 7. - R means to take the upper
+half, keeping columns 4 through 7. - L means to take the lower half, keeping
+columns 4 through 5. - The final R keeps the upper of the two, column 5.
+
+So, decoding FBFBBFFRLR reveals that it is the seat at row 44, column 5.
+
+Every seat also has a unique seat ID: multiply the row by 8, then add the column. In
+this example, the seat has ID 44 * 8 + 5 = 357.
+
+Here are some other boarding passes:
+
+- BFFFBBFRRR: row 70, column 7, seat ID 567. - FFFBBBFRRR: row 14, column 7, seat ID 119. -
+BBFFBBFRLL: row 102, column 4, seat ID 820.
+
+As a sanity check, look through your list of boarding passes. What is the highest seat ID
+on a boarding pass?
+
+