Directory structure

.
├── <year>
│   └── <day number>p<part number> 
│       ├── puzzle_input.txt <- Actual puzzle input (but i wont track it on github)
│       ├── main.c           <--- main.* is the solution
│       ├── main.lua         <-|
│       └── test_input.txt   <- Test input 
...

Programs will read input from stdin and output sole result on stdout
Run it like `./main.lua < input_file.txt`

Ouput is just a singular number  

For C codes its usually can be compiled with `gcc -Wall main.c -o main` (the code runs/compiles on POSIX compliant compiler and OS)
or run with ./main.c (its bash and C polyglot)
For Lua codes its runnable with `./main.lua` (chmod it if necessary and requires lua5.4 installed)

Should always be compile/run from terminal not from IDE build option