Day 16: Ticket Translation

Classes:

RuleParsing(identifier, ranges)	Represent a rule which is not constrained by pre-conditions.
Rule(identifier, ranges)	Represent a rule for the ticket field.

Functions:

applies(rule, value)	Check whether the rule applies to the value.
parse_rules(lines)	Parse the lines into rules.
parse_nearby_tickets(lines)	Parse the nearby tickets from lines to list of field values.
invalid_fields(rules, ticket)	Select the invalid fields from a ticket according to rules.
list_all_invalid_values(rules, tickets)	Select the invalid fields accross all tickets according to rules.
compute_error_rate(invalid_values)	Compute the error rate as sum of the invalid values.

class RuleParsing(identifier: str, ranges: List[Tuple[int, int]])

Represent a rule which is not constrained by pre-conditions.

Methods:

__init__(identifier, ranges)

Initialize with the given values.

Attributes:

identifier	Identifier of the field
ranges	Valid range of values for the field

__init__(identifier: str, ranges: List[Tuple[int, int]]) → None

Initialize with the given values.

identifier: Final[str]

Identifier of the field

ranges: Final[List[Tuple[int, int]]]

Valid range of values for the field

class Rule(identifier: str, ranges: List[Tuple[int, int]])

Represent a rule for the ticket field.

Methods:

__init__(identifier, ranges)

Initialize with the given values.

Attributes:

identifier	identifier of the field
ranges	acceptable ranges for the field

__init__(identifier: str, ranges: List[Tuple[int, int]]) → None

Initialize with the given values.

Requires

• all(range[0] < range[1] for range in ranges)

• len(identifier) > 0

identifier: Final[str]

identifier of the field

ranges: Final[List[Tuple[int, int]]]

acceptable ranges for the field

applies(rule: Rule, value: int) → bool

Check whether the rule applies to the value.

parse_rules(lines: Lines) → List[RuleParsing]

Parse the lines into rules.

While the parsed rules are syntactically correct, they have to be yet semantically verified.

Requires

• all(RULE_RE.match(line) for line in lines)

parse_nearby_tickets(lines: List[str]) → List[List[int]]

Parse the nearby tickets from lines to list of field values.

Requires

• all(
      re.match(r'^(0|[1-9][0-9]*)(,(0|[1-9][0-9]*))+\Z', line)
      for line in lines
  )
  

invalid_fields(rules: List[Rule], ticket: List[int]) → List[int]

Select the invalid fields from a ticket according to rules.

Ensures

• all(
      value in ticket
      for value in result
  )
  

list_all_invalid_values(rules: List[Rule], tickets: List[List[int]]) → List[int]

Select the invalid fields accross all tickets according to rules.

Ensures

• all(
      any(value in ticket for ticket in tickets)
      for value in result
  )
  

compute_error_rate(invalid_values: List[int]) → int

Compute the error rate as sum of the invalid values.