file = open('input.txt','r')

passes = file.readlines()

def getRow(code):
    high = 127
    low = 0
    for c in code:
        print('Row Char: '+c)
        if c == 'F':
            high -=int( (high - low + 1) / 2)
        else:
            low +=int( (high - low + 1 ) / 2)
    print('low: ' + str(low) + ' high: ' + str(high))
    return low

def getSeat(code):
    high = 7
    low = 0
    for c in code:
        print('Row Char: '+c)
        if c == 'L':
            high -=int( (high - low +1) / 2)
        else:
            low +=int( (high - low + 1) / 2)
    print('low: ' + str(low) + ' high: ' + str(high))
    return low



maxSeat = 0
seats = []
#passes = ['FBFBBFFRLR','BFFFBBFRRR','FFFBBBFRRR','BBFFBBFRLL']
for p in passes:
    row = getRow(p[:7])
    column = getSeat(p[7:10])
    seatID = (row * 8) + column
    seats.append(seatID)
    print(p)
    print('row: '+str(row))
    print('col: '+str(column))
    print('seat: '+str(seatID))
    if seatID > maxSeat:
        maxSeat = seatID

last = 0
preLast = 0
seats = sorted(set(seats), key = lambda ele: seats.count(ele))
#seats.sort()
for s in seats:
    print(str(last) + ' vs ' + str(s))
    if s - 1 != last and s == last + 2:
        print('hole between ' + str(s) + ' and ' + str(last))
    preLast = last
    last = int(s)
#print(str(maxSeat))