Binary_boarding_day5

with open ('Day5.txt', 'rt') as f:
    data = f.read().strip()
data = data.split('\n')

#part 1
def find_position(code,  start, end, left, right):
    for value in code:
        if value == left:
            end = (end + start)//2
            final = end
        else:
            start = (start + end)//2 + 1
            final = start
    return final

def find_id(code):
    rows = code[:7]
    row_final = find_position(rows, 0, 127, 'F', 'B')
    columns = code[7:]
    col_final = find_position(columns, 0, 7, 'L', 'R')
    return (row_final * 8 + col_final)


max_id = 0
for seat in data:
    max_id = max(max_id, find_id(seat))
print(max_id)


#part 2
seats = set()
for seat in data:
    seats.add(find_id(seat))
all_seats = set()
for i in range(min(seats), max(seats)+1):
    all_seats.add(i)
print(all_seats.difference(seats))