def part1():
def is_valid(line):
for field in REQ_FIELDS:
if field not in line:
return False
return True
return len([chunk for chunk in read_chunks("Input.txt") if is_valid(chunk)])
def get_tiles():
chunks = read_chunks('Input.txt')
tiles = [
Tile(int(tile[tile.index('Tile ') + 5:tile.index(':\n')]),
tile[tile.index(':\n') + 2:].split('\n')) for tile in chunks
]
for tile in tiles:
populate_edge_matches(tile, tiles)
return tiles
def part2():
def get_field_index(line, field_name):
try:
return line.index(field_name)
except ValueError:
return -1
def parse_value(line, field_name, total_length):
field_index = get_field_index(line, field_name)
if field_index == -1:
return False
if len(line) < field_index + total_length:
return False
field_and_value = line[field_index: field_index + total_length]
return field_and_value[field_and_value.index(':') + 1: len(field_and_value)]
def valid_year(line, field_name, start_year, end_year):
value = int(parse_value(line, field_name, 8))
if not value:
return False
if start_year <= value <= end_year:
return True
return False
def valid_eye_colour(line):
valid_colours = ['amb', 'blu', 'brn', 'gry', 'grn', 'hzl', 'oth']
value = parse_value(line, 'ecl', 7)
if value and value in valid_colours:
return True
return False
def valid_hair_colour(line):
valid_chars = '0123456789abcdef'
value = parse_value(line, 'hcl', 11)
if not value:
return False
value = value.rstrip()
if len(value) == 7 \
and value[0] == '#' \
and all(c in valid_chars for c in value[1:len(value)]):
return True
return False
def valid_passport_id(line):
value = parse_value(line, 'pid', 14)
if not value:
value = parse_value(line, 'pid', 13)
if not value:
return False
value = value.rstrip()
if len(value) == 9 and value.isdigit():
return True
return False
def valid_height(line):
field_index = get_field_index(line, 'hgt')
if field_index == -1:
return False
value = line[field_index + 4:len(line)]
if 'cm' in value:
value = int(value[0:value.index('cm')])
if 150 <= value <= 193:
return True
elif 'in' in value:
value = int(value[0:value.index('in')])
if 59 <= value <= 76:
return True
return False
def is_valid(passport):
valid = valid_year(passport, 'byr', 1920, 2002) \
and valid_year(passport, 'iyr', 2010, 2020) \
and valid_year(passport, 'eyr', 2020, 2030) \
and valid_eye_colour(passport) \
and valid_passport_id(passport) \
and valid_hair_colour(passport) \
and valid_height(passport)
return valid
return len([chunk for chunk in read_chunks("Input.txt") if is_valid(chunk)])
def part2():
def populate_possible_field_map():
for position in range(0, len(number_rows_ints[0])):
all_possible_fields = set()
for number in [
number_row[position] for number_row in number_rows_ints
]:
this_number_fields = []
for valid_row in valids:
field_name_and_ranges = get_valid_range(valid_row)
ranges = field_name_and_ranges[1]
if int(ranges[0][0]) <= int(number) <= int(ranges[0][1]) \
or int(ranges[1][0]) <= int(number) <= int(ranges[1][1]):
this_number_fields.append(field_name_and_ranges[0])
if len(all_possible_fields) == 0:
all_possible_fields = set(this_number_fields)
else:
all_possible_fields = set.intersection(
all_possible_fields, this_number_fields)
position_to_field_names[position] = list(all_possible_fields)
def remove_definitely_known_fields():
for key in position_to_field_names.keys():
if len(position_to_field_names[key]) == 1:
for other_key in position_to_field_names.keys():
if key == other_key:
continue
position_to_field_names[other_key] = [
entry for entry in position_to_field_names[other_key]
if entry != position_to_field_names[key][0]
]
chunks = read_chunks('Input.txt')
valids = chunks[0].split('\n')
number_rows = chunks[2].split('\n')[1:]
completely_invalid = find_completely_invalid(valids, number_rows)
remaining_number_rows = [
number_row for i, number_row in enumerate(number_rows)
if i not in [valid[0] for valid in completely_invalid]
]
number_rows_ints = [row.split(',') for row in remaining_number_rows]
position_to_field_names = {}
populate_possible_field_map()
# Now go through the map, find positions for which we definitely know the field, and remove that
# field from all the other positions. Keep doing that until all positions have only one possible field
while len([
fields
for fields in position_to_field_names.values() if len(fields) > 1
]) > 0:
remove_definitely_known_fields()
departure_positions = [
key for key in position_to_field_names
if 'departure' in position_to_field_names[key][0]
]
my_rows = [
int(num_str) for num_str in chunks[1].split('\n')[1:][0].split(',')
]
return math.prod([
num for index, num in enumerate(my_rows)
if index in departure_positions
])
def part1():
chunks = read_chunks('Input.txt')
valids = chunks[0].split('\n')
number_rows = chunks[2].split('\n')[1:]
return sum(
[result[1] for result in find_completely_invalid(valids, number_rows)])
def part2():
return sum([get_all_yes_count(chunk) for chunk in read_chunks("Input.txt")])