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 - 20th December 2020

1. Find corner tiles of a puzzle and multiply their tile ids.

2. I have not worked on part 2.

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.

Here is the solution for part 1:

Overview of all solutions of 2020:

Advent of Code 2020 Solutions Overview