16th December solution - Advent of Code 2020 - swift
As part of Advent of Code (adventofcode.com) each day there are two programming tasks to be solved. All solutions are listed here.
I am writing the solutions in Swift with the Playground environment in xCode.
Tasks - 16th December 2020
Find all invalid tickets and sum up all the invalid field values.
Match the rules to the order of the values on the ticket and multiply all fields of my ticket starting with "departure".
For a more detailed description of the tasks check this out.
The lines variable is an array of lines in the txt files given to each member by Advent of Code, which is individual for each user.
The solutions are a continuation of each other so the solutions are not split. Here is the solution: