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-# advent-of-code
-Solutions for Advent of Code in 2024
+# Advent of code 2024
+
+These are my solutions for Advent of Code in 2024.  This year I'm using Lua as the programming language.  To launch the program for a given day, run
+
+```sh
+./main <<ID>> [<<FILE>>]
+```
+
+where `<<ID>>` is the day number followed by `a` for the first part or `b` for the second part, e.g. `01b`.  If the file is not specified, it default to the number of the day with two digits and extension `.in`, i.e. `01.in`.  One can use the name of a file that doesn't exist, e.g. `-`, to read from standard input.